Your best is not enough, until people get to acknowledge your best. You called your best, best because your are at your threshold, often time is yet to be good. Pushing a little harder will make you go beyond your usual THRESHOLD. Working on your good makes you better. Threshold is a point where when exceeded more than what you can afford will be required, it's beyond your usual stamina which often leaves you strained or stressed out but with new attained threshold.
Thresholds shrinks and also can be expounded. Fear can result in both, it can shrink the threshold perpetually and likewise expand the threshold momentarily. Allowing fear to engineer your threshold is not cool. Taking conscious effort to surpass your threshold is the real thing, and wherewith a new threshold is possiblely attained. The conscious effort will make you attain new threshold, maintain it and on the long run push the threshold further.
One needs to keep pushing his/her threshold over and over again. You can, following a common saying "good, better, best, I will never rest, until my good is better now then I can rest". Not giving up, but pushing enthusiastically is essential. Often times an intrinsic motivation is not enough but the need to get motivated by external forces. Whether external or intrinsically, motivation is necessary for the push to happen and also to be successful in attaining new threshold in life