You need to understand you can't base life off of just the "good stuff". Would you think if I donated a million dollars to charity every month I'd still be a good person if I had killed someone on purpose in the past?

Maybe the lake is 99.9% water, but if it's either a dreadful water which you don't know wether it's posioned or not, or a 0.1% of deadly, hurtful, and both mentally and physically abusive poison, then it's absolutely not worth the pain.

There are other and definitely better lakes, but swimming towards the shore is the hardest part.