Hidden weaknesses can bring down huge structures. Hidden character defects can bring down otherwise strong people. 

In Judges 14 we encounter the strongest man who ever lived, but before his physical strength is revealed, his inner weaknesses are. By the time the chapter is over, we will see his inner weaknesses getting him into the trouble that will eventually be his downfall.

Samson wasn't the last strong person with hidden problems. None of us want to fail like he did. That makes his story relevant to us.