Yeah the Vault design is just stupid. You can do first three floors and get 60% or you can try floor 4 and if Immortals kill you everything is lost so why risk it? Really as an immortal, 95% of the times I get to defend its a bunch of noobs who did not know they should skip and we murder them with ease and 5% it's the top shadows who will eventually unseat us and they pretty much are prepared and murder us since they are just waiting there for us to spawn with all CDs and everything rdy.