Nobody is excellent at everything they do.

A savant in the negotiation room might be a miserable lover.
A best-selling author might have a hard time speaking to a crowd.

As we are, at this moment in time, we’ve developed several specific skills and talents more than others. That doesn’t mean that what we’re good at is a fixed list, though.

What we’re bad at now, we might become excellent at in the future.

“I’m bad at that” doesn’t make any sense.

What we mean to say is,
“I haven’t dedicated myself to that, yet”, because, the truth is, if we prioritize the development of something, we won’t be bad at it for very long.