If you forget something for church and you are already in the driveway with the car running do not take your house key off your key chain to run back in and not reattach it. Later you'll go to your sisters for dinner and realize you do not have a key to get back into your house when you arrive home. Then you'll have to go next door to your neighbors and attempt to get a locksmith out on a Sunday night, none of which will come. Your neighbor will then try to help you jimmy your lock to no avail. You'll then have to take your screaming child, who has missed his bedtime, back to your sisters. You'll leave your wife and child there to meet the fire department, who says they do lockouts, at your house. They won't be able to get in and you'll come back still locked out. Finally, you will be able to contact a locksmith who will meet you at your house and for $150 you'll finally be able to get back in. So, for everyone - that extra key you've been meaning to hide in the garage or give to your neighbor, go ahead and do it this week!