Does anyone else ever wonder whether you're any good at what you do? Whether people are telling you your work is good just to humour you and that actually you are awful.
If this were the case, I would rather someone came to
me and said, "actually, mate, you could have done better/this was what I was expecting you to be able to do/next time would you be able to...?" This then gives me the opportunity to ask what it was that I lacked, what I need to start doing and where I can work to improve. This feedback may also give some explanation as to why you aren't being offered any work, you’re being offered less work or you may be being replaced. It can feel a bit rubbish if this is happening and you don't know why.
So when it comes to telling someone about how they are performing, honesty is always a good idea. This can be a minefield though. If someone is performing well, then it is not hard to be honest. "Keep up the good work Bob." But if a performance leaves something to be desired, particularly when it comes to the arts, it is hard to be honest. You don't want to hurt feelings and you don't want to put people's noses up either. It's hard to say "You’re not really cut out for this Bob."
This is where the recipient’s attitude can be dissuasive of honesty. Perhaps due to vanity, pride or a negative attitude to work, a person may not appear willing to accept an honestly negative opinion of what they are doing. If this is the case, people won't give negative opinion for fear of getting an unpleasant reaction. It is always the case that not everyone likes everything. So I you seem to be getting all good reviews then someone is lying.
Even if a person doesn't seem to have an overly negative attitude to criticism, it can still be hard for someone to come out with it.
So if you do want to hear criticism, you need to invite it.
But then if you don't want to hear criticism, perhaps you need to hear it!
Even after you ask someone their honest opinion and by some miracle they give it, attitude and humility are still important. If you ask for some criticism, you expect it in some areas, for certain things you feel maybe aren't up to scratch. But then a critique of something you thought was fine, or even good, arrives it can knock you sideways and leave sour feelings. You invited it so you shouldn't blame them if you hear something you don't like. You need to consider that the blows may land where they're least expected, so be prepared to receive a blow that could land anywhere.
Prepare for the worst, hope for the best.
You then need to make sure you haven't reacted in such a way as to have discouraged future criticism. And listen to it too, make a note. That way you can refer back to it and see if you have improved on the point(s) given.
In answer to the question I set as the title to this post: ask. Fairly often too. The more feedback you get, the more accurate a picture you get of how you work and where your flaws are.