It's Halloween Again?

I KNOW I'm not the only mother out there who pulls together Halloween costumes for the kids 10 minutes before they need to get to school/party/go trick-or-treating.  So why can't I learn my lesson and INSIST on doing this year after year?  I've made kick-ass costumes in the past - why don't I just do it again?? No I MUST make it as stressful and uninspiring as possible! At least I'll get candy.