Why is Baptism "Bad" ? is it harmful or just water? (honest question from an idiot who can't bother to google)

[PullusPardus]

I'm not christian, never been, I've seen a lot of people refuse Baptism like its harmful, isn't it basically just taking a fee bath with a dude murming random words?

is it harmful? like for example Circumcision? do you have to cut your dick like shwarma to be Baptised?