Badge vs Insignia

Maybe a silly question but why do most classes prefer Insignia over Badge?

I get that for most classes haste is better then crit, but surely having the stat boost on demand to line with cooldowns is better then a random proc?

I play survival hunter for example, my 1 Min takedown is when i do dmg, I do negative dmg in between goes so having a random proc on Insignia, I dont see how thats helpful?

Thanks