[Panser]

My personal experience is that if a ship is damaged enough to drop any lifeboats, it will go down eventually. On a slow sinking of a large ship you will quite often get one or two released very early. Once you get about three dropped simulatenously the ship is likely on it's way to the bottom very soon after.

I think this is a nice touch actually as there are plenty of accounts of lifeboats either being manned in a panic long before or ship sinks or even having to return to a ship with egg on their face because it remained afloat and serviceable.