Impatient (3.5e Flaw)
From D&D Wiki
You find it simply unbearable to wait any longer than necessary.
Effect: You take a -4 penalty to all craft, move silently and hide checks and cannot delay actions. Furthermore, any spells with a casting time greater than instantaneous are cast with a -1 penalty to caster level.
Roleplaying Ideas: You were born with the inability to wait, whether it be severe or minute, you are constantly at war with time. While others might seek to take something slow and carefully, you would much rather see the consequences quickly by rushing into the situation head on.