Worst Case:Just for a moment, imagine that you are the worst player on your team, but nobody tells you because they don't want you to feel bad. All the other programmers are fixing up your code so it works, your design sense is flawed, and everyone knows it but you.
Then you find out.
Of course, you'll have a sinking feeling and probably get mad. Let's say for a moment that quitting is not an option. The question is "what are you going to do about it?"
For some people the initial response would be shame and anger and abuse of one comforting substance or another (likely liquor, but possibly pizza, cookie dough, or a tub full of Mr. Bubble). At some point you will realize that you have to go back into the office.
Everyone there already knows. It is likely that they have heard that you found out. Now what? You could get discouraged but that's hardly helpful. There is only one thing to do: you have to get better.
What is the plan? How will you pick up on new skills and design sense? You could isolate and read, but that's not going to work during business hours. You can read more code, but you do need to produce something and you need the practice.
Likely CaseNow, imagine that you're a solid player. Everyone knows it, and nobody needs to tell you.
Then you find out that there are programmers in the world who could do what you do better, faster, easier. What is the plan?
I suspect you would do the same things to improve, only this time without shame and humiliation. You would do some research, try things differently, read something, get a second opinion, find a mentor.
Your CaseGuess what? You're probably a pretty good performer.
Still, there are guys out there who can do what you do a little better, faster, or easier.
What are you going to do?