Question

Will the earth be all sea one day?

Answer 1

Maybe! - its a race between competing processes that may lead to a water world, or even snowball Earth, or desert Earth.

Answer 2

It is race b/w competing processes that,they may lead to water world,snow world,desert earth,e.t.c...,but nothing can stop ceasing of tectonic plates,and soil erosion,so the earth may be all sea one day,or anything.