With the sheer size of NFL rosters, there are guaranteed to be weaknesses somewhere, and the Chargers are no exception this year, (looking at you, offensive line) but hiding your weakness is very different depending which side of the ball you’re looking at.
Offensively, you can’t always hide a quarterback’s deficiencies, but there are measures that can be taken to avoid them rearing their head more often than they need to. Playbooks that employ higher percentage throws, shorter drops, route concepts that require less anticipation, read-option to freeze the defense etc. Arm strength, athleticism, football IQ, whatever the short coming is, it can be mitigated to a certain degree.