Locked doors while you are home

So this may not be super controversial but it kind of goes along with the guns for protection thing.

Do you keep your doors locked or unlocked while you are home?

Bugs the hell out of my husband that I keep the garage door down and our doors locked because he says it is unnecessary while I'm home to do both. I personally would rather have my doors locked. I don't trust anyone, especially the loons around here to not knock only and wait for someone to come to the door. I've just always been that way since having my own home. My parents always had the front door open because family would always visit