Why sweat smells?

There's good bacteria. There's bad bacteria. The shit from sweat must be bad, coz BO and sweaty feet smell fair atrocious, and we wash it off. Except for some people on public transport who don't seem to mind their own stench.

Excercise is good for you. Keeps you fit. Makes your body look better.

Sweat excretes pheremones. Attracts the opposite sex.

So, long story short..... Excercise is good for you and a sweaty man:
BITCHES LOVE THAT SHIT!!!

So why does sweat make a bad smell??