What does a workaholic do on vacation? How does a workaholic know when vacation’s over? How hard does the rain have to fall? I can still remember the first day of school after summer, pretending not to be excited, but secretly so happy to be back behind a desk, the smell of new supplies, new books, watching a new teacher try to make an impression. My mother’s sandwiches in tin foil, a piece of fruit banging around in my lunch box. I did four loads of laundry when we got home and walled off.
When you say you’re not good at something, what do you mean?
Betsy Lerner 
I’m not good at most things, but I’m not mean about it.
“When you say you’re not good at something, what do you mean?”
That I accepted my perceived limitations, which perceptions almost always arise from experience. That the evaluation of the experience can be subject to adjustment is a question some leave open and others do not.
Sometimes, when we say we’re not good at something, we mean the subject never interested us enough to try to become good at it. But I see myself entering a hall of mirrors here. Was there some key that might unlock our interest, and we never found it, or never were presented with it? Did we never seek, that we may find? If I had ever sought and found a way to master the F major chord, would I have continued with my studies in learning how to play the guitar? Why did I not just ‘power through,’ finding a way around or over the difficulty? Why did I not just say, ‘F*ck it, I’m going to play this guitar any way I can?”
Is there anything any one of us cannot in some way do, if we are determined enough? If we have time enough? How’s your left foot? Am I the monkey who will write Shakespeare? Do I look good in this light?
I try not to say that I’m not good at something, except to myself. What I mean is that someone else is better, anyone is better. It’s hard not to compare to others. It’s one of my life goals.
Usually, I mean exactly that.
Whatever “it” is, I recognize it and don’t mind admitting it. Like, I’m terrible at remembering names. (who isn’t?) I’m terrible at condensing what I want to say, and tend to go down rabbit holes on the way to what I want to say, and sometimes even lose track of the point as I meander about in the rabbit hole. Etc.
It’s a good/bad thing to know/admit weakness. It can instigate a biased opinion, or draw empathy.
math
My wife speaks her mind, rarely censoring herself if she has something to say, especially in response to racism and intolerance. “I’m not very good at keeping quiet when someone says something I disagree with,” my far better half has said. I think her responses are usually close to perfect. Sometimes it just depends on what you’re not very good at.