higer kv lower kv whats it all about

dumb question here be here it goes.i know you guys say that a lower kv motor and higher volt battery will make a motor and battery stay cooler, but say a i have a motor say 3000kv on a lower volt battery 14.8 at 15c ,will that
work.i am new to this brushless thing still trying to learn a few things. and i know you guys know your stuff,because i have been reading here for a while.
thanks.