Some have been poignant: sometimes learning from other people's mistakes costs less than learning from your own.
Some have been not so poignant but still ultimately helpful: remember to check your bank account before making big purchases.
It is in this vein that I present to you, Sarah's life lesson #847: always listen to your hair stylist. Especially the week before your sister's wedding.
What are some life lessons that you've learned? Care to share so we can avoid unnecessary pain? Have you learned any recently?