Sandcastle Mentality

Acceptance of inevitable destruction.

When you know that something is inevitably going to ruin what you have done, but you do it anyway for whatever reason you may have.

Quoted from 2b2t wiki:
The Builder's Dilemma, The Sandcastle Mentality is a philosophical concept that is one of the pillars of the "veteran mentality". It means that a player accepts the destructive nature of 2b2t, and learns to live with it. Its name comes from building sandcastles on beaches: no one builds a sand castle believing or expecting that it will last forever.

"Mark built a sandcastle even though he knew a wave will just wash it off at some point. One can say he has the Sandcastle Mentality, maybe even a Builder's Dilemma in mind."