We should care about the big things and probably got to allow for mistakes in the small.
Certain small mistakes, however, must be avoided. One can nimble endlessly, and consider each bit a "small" mistake.
An interesting point is why not consider every small mistake as part of the accumulation of things in life. Certainly, it is good to do the right thing every time. But it must be assigned the right weight. There is more to it, but no mood to think now.