No matter what kind of ethical system we have, for the most part, most of us will be unable to live up to that ethical standard 100% of the time.
Part of the issue arises from defining ethics in an almost entirely inflexible way. We establish rules without necessarily establishing conditions for those rules, and this then brings us trouble.
The trouble arises like this: certain circumstances with certain conditions arise. Someone develops a rule on how to handle that set of circumstances.
Later on, a second set of circumstances arise with somewhat different conditions that are unaccounted for in the first set of circumstances. People generally still attempt to apply the standards and rules for the first set of circumstances in the name of integrity, and if one doesn't, well. Watch out.
I've opted to go with tailoring the rules to the circumstances while keeping their spirit. This is, after all, the sensible thing to do, and we've no problem doing these things in situations regarding good manners and proper etiquette. (The example here is that in the USA, men typically remove their hats indoors, but when one attends Jewish services, a man covers his head indoors. The religious protocols override the typical protocols).
The same has to be applied to ethical standards. That doesn't mean one goes around constantly defying what one professes- which is a reality we see far, far too often in our world.
Let us strive to be good people. Let us strive to be numbered among the virtuous.