Character is not built in the smooth sailing. It is not built in anything that is something from the outside. Character is built in the course of inner confrontation. When we struggle against pride and sin we find the ability and resolve to overcome. That is the place of character.
David Brooks in his book The Road to Character says this:
Character is a set of dispositions, desires, and habits that are slowly engraved during the struggle against your own weakness.
Character is developed through a thousand small acts of self-control. If we do not handle the inner frustrations, anger, anxieties well, the core begins to crumble. Our inner life decays.
Character is long term. Lust, pride, other sin will corrupt long term and lead to short term AND long term failure.
To paraphrase Eugene Peterson a bit, the building of character is a long obedience in the same direction.
Build from within. Start small. Conquer the inner person. Character comes.