Yes, mine! In fact I posted something similar just last week, so I have no real advice. Someone suggested I remind DD1 of something she can now do that she couldn't previously, which is why I intend to try. For the first time this morning, when normally she'd say "I don't like ballet because it's too hard" before her lesson (which she always enjoys regardless of what she says) she said "I am going to try hard in ballet, so that I can get much better at it". Almost like it's clicked that sometimes you just need to work and it can take time.
My ds six is a real perfectionist. He seems a bit scared of failure and can get upset if he doesn't win or isn't the best.
Ironically I grew up with an emotionally abusive father who lived through my success and I have always strived not to be pushy with my kids. I encourage them and praise them lots but I hope they know I love them regardless. I tell them it is okay to make mistakes but I am strict about rude or cheeky behaviour.
So I worry about why my ds is like this. He is very bright and loves music, quite mature for his age I suppose.