The problem would be when the water level in the cockpit was able to run into the boat via the companionway or a cockpit locker... It would take a long time but eventually it could sink... but in the meantime you'd have a lot of water below with all the attendant damage from that.
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)
1984 Fast/Nicholson 345 "FastForward"