You're the expert on game design, but other people are the experts on whether they're having fun or not. You have no objective but to make them have fun, if you want to be successful.
If you are unable to accept and utilise feedback about your games, your chances of success in this industry are virtually zero.
Don't just accept
feedback. Embrace it. Consider yourself a chef, only trying to please
your customers. Your game is as good as your playtesters say it is.
When you receive feedback, resist the urge to defend your game, explain, or disagree. It might sound obvious, but you can just not enact their feedback if you don't agree with it. You don't need to win the argument. Get into the habit of just listening to people.
People will give you outrageous and clearly wrong suggestions that tear at the very heart of your game. However, you will very often mull over their feedback later, and decide that there was real merit in what they were saying. Something you thought "had to be that way" really can be changed. This might sound unusual, but trust me. I've done it, and seen others do it. You'll do the same. A kind of self-doubt can be very useful here. "What if they're right..."
You should be accepting most feedback you receive.
Playtesters are better at seeing problems with your game than you are. And, at the end of the day, you're designing for other people, not for yourself. The broad group of "other people" who comprise your playtest group are similar to the "other people" who will end up playing your game once it's released.
Feedback from people who are non-gamers is the worst feedback of all. Their feedback is not relative to other games, and is typically very positive. Some kid who's never played Magic will likely think your Magic knock-off is fantastic, and you'll believe them. Publishers will think it's terrible.
Gamer friends make great playtesters, but they're far from impartial. They're invested in the project, as a design. They've been part of the process, and helped make (or miss) the game's mistakes. Also, they're a self-selected group, who are biased towards liking the game.
"Fans" are the worst playtesters. I've seen people with flawed or mediocre games cobble together a die-hard group of fans in a Discord chat server. These people help with the game, and have the designer believe that their love of the game is shared by the wider public. In reality, these people are a fringe minority, sifted out of hundreds of potentials.
Unknown people at a games club, or online, are some of the best
testers. They have the least to lose, by being the most honest with you.
It can be hard to put your game out "into the wild" like this, but
playing it with random gamers should be done towards the end of every
design. Do not do this, and then write those people off!
The best testers are "blind" playtesters. These are people you don't know, and have no contact with. Get a friend to give your game to their other friends. They have zero connection to you, and have no reason to be polite. Blind playtesting is not easy to organise, so you'll need to do most of your late testing with the aforementioned unknown people. Blind playtesting is typically used at the end of design, to ensure that players can learn a game solely from its rulebook.
If a publisher plays your game, rejects it, and gives you feedback,
take this feedback as gospel. You cannot afford to waste another
publishing opportunity. Do not just send the game to another publisher.
Whether you think so or not, your game is not close to publishable. Do
significant work on the game, and then try again.
If you can't
understand or fix what the problem with your game, you need to go and
do something else, and put this game on the shelf for a while. The game
may simply not be good enough, and therefore not fixable.
It's easy to get good feedback about some parts of your game, relative to the rest of your game. People will point out the bits they don't feel work, or fit in.
People want to be helpful. You've chosen your direction, and they want to help you with it. It might be the wrong direction, but they don't feel it would be helpful or polite to tell you to do something totally different.
It might actually be useful to say that the game was terrible. They don't consider that you would abandon your game, no matter how bad it is.
Consider the playtesters' actions, not their obligatory polite verbal
statements. "I like the game" and "that was good" mean absolutely
nothing.
What you're looking for is "let's play again", unprompted by you. If they ask to play it later, that's even better.
At all stages of the development of Radlands, people were asking when they could buy it. They didn't have to say that, to be polite. If you're not getting "let's play again" or better, your game isn't good enough.
This is a very important point: negative feedback is really the only useful feedback. Positive feedback is fantastic, but you can't usually act upon it. Negative feedback is a gold nugget of new insight.
I interrogate playtesters, specifically asking them for negative feedback. "What part was the least fun?" is a great opener for negative feedback. I'll sometimes add "was it boring, too complicated... too long... not interesting enough?" This specifically asks for criticism, and the criticism doesn't denigrate the whole game, just the least fun bit. It also isn't asking the player to analyse the game — only their own feelings. It's your job to cater to those feelings.
A good designer is like an airline pilot. If something's wrong with my work, I absolutely want to know.
I want to succeed. I'm wrong about things all the time, and I want to know when I am.
It took me a while to develop this attitude. To be fair, it's much easier to take negative feedback when you're a good designer. It's also easier to subject your games to rigorous scrutiny when you're confident they're solid, or comfortable with abandoning them.
For my games in late development, it's great news when a playtester finds something negative to say.
Players often can't even identify their specific negative emotions about a game, let alone diagnose their cause.
When testing my own games, I'll often see a problem, and point it out to the tester after the game. They didn't identify this problem themselves, but they jump to agreement with my point, because they felt it too.
Playtesters often don't even know that the game is even supposed to be great. If I showed you a painting I'd painted, would you expect it to be great, and judge it by art gallery standards? In board game design, that's precisely what I'd want.
Playtesting itself is a skill, and you need to "train" your playtesters. Tell them how to give feedback.
I often give feedback to people about their games, only to find out they haven't received any serious (negative) feedback before. Their game has fundamental problems, but the feedback they've received only dealt with minor issues.
I've had so many cases where I tell a game designer that there are fundamental problems with their game. Two weeks later, the designer is "just finishing up the design, ready for publication", with none of the issues I raised addressed. The game is basically as it was before. When I make a criticism, I'm not necessarily right, but I'm a pretty good designer (and now a published designer) — at least as good as the other designer. What's the chance that if I say there are big problems, then there just might be a problem of some kind? This goes both ways — when someone tells me there's a problem with my game, I take that feedback very seriously.
It's very easy to live in a fantasy world, where your game is excellent, and you dismiss criticism of it as just personal opinions of uninformed outsiders.
Some designers have told me that they've found (or believe exist) people who are hugely attracted to very specific combinations of mechanics, or theme and mechanics. They cannot make some minor change to the game, because this mythical cohort wouldn't like it.
Maybe you just want to do your own thing, without outside input. That's fine, but you're going to be taught a lesson the hard way, when your game fails or sucks, or just gets lost in a sea of other mediocre games.
The annoying thing about people who fail to take feedback is that they're doomed, but they'll never know it. You can't convince them otherwise, because neither of you are published designers. The only proper evaluation you can ever get as a designer is to get published. I wanted to get published, so I knew I was clear of this fatal error, and others. Until that point, I was probably just like them, only with different errors.
Another strategy is for a designer to counterpose their negative feedback against the positive. I say "I don't like how that works", and the designer says "Other people like it." My criticism in these cases was valid, I assure you, but the designer wanted to be right, more than they wanted to make sure their game was good.
Positive feedback does not cancel negative feedback.
I've repeatedly made the mistake of assuming others want blunt, no-nonsense, negative feedback. I spend two hours playing someone's game, and then I eviscerate it. I just can't do anything else. Everyone else has lied to that person, failed to have any standards, or watered down their feedback in some way. Except me.
When I tear apart the fundamentals of their game, they often ask for how I'd do it differently. I usually can't say. This isn't a valid question from the designer, however. It's not my job to fix their weak game, and the fact that they can't do any better is not an excuse. This conversation often gets a bit tense. I'm always happy to discuss things later, by message, and patch things up.
In a way, I'm still not telling them the whole truth. The correct answer for the majority of games I play is to scrap them. I scrap most of my own games, after all. I just can't tell people to scrap their games. Not immediately, anyway. What's the chance that the game is in the top fraction of 1% of designs, that get published, or even the top 5% that could get into the top 1%? Not much.
I always took the view that this relative honesty was the best policy, but I've come to the realisation that it probably isn't.
The key thing that changed my mind is that almost none of these people are going to be successful anyway, so I'm really just being a jerk, and ruining their fun. If their game is decent, I'll likely be more helpful. For the rest, who literally have a sub-1/1,000 chance of publication, it's best to leave them to their hobby.
With my regular playtesters who are also designers, I know where they're coming from, so I'm always honest with them.