…if you wish not to be disappointed in your desires, that is in your own power. Exercise, therefore, what is in your power. A man's master is he who is able to confer or remove whatever that man seeks or shuns. Whoever then would be free, let him wish nothing, let him decline nothing, which depends on others; else he must necessarily be a slave. - Epictetus
There is a certain freedom, and even power, that comes with making the approval of one’s conscience the litmus test for one’s actions. If I give public opinion or other external indicators of success precedence over the dictates of conscience, I make myself subservient to forces I can’t control (or even entirely trust). This is a recipe for anxiety, disappointment, and eventual despair. Even if I do find success, it is always temporary and often unfulfilling by itself.
This is not to say that seeking success is wrong, or that others' opinions are irrelevant. In fact, it is one of our moral duties to strive to better ourselves and flourish in such a way that benefits others. But if we define success purely in terms of external markers, such as wealth or public opinion, then we enslave ourselves to those forces. We are crushed when we don't receive the praise we feel we deserve (even though we may really deserve it), and we collapse under the weight of failure when our plans are derailed by factors completely outside of our control.
The only sure path that keeps us free from the whims of chance and public opinion is to define success first and foremost in terms of the approbation of conscience. Our moral sense isn't perfect, but it's the best faculty we have for navigating the phenomenon of existence. If we define success in terms of the peace that accompanies a clear conscience, we are never subservient to any force except the one that counts.