On the other hand, for the purposes of this comic, if the purpose of the lock is to keep someone from walking in on your solo sex act, then a lock that takes 5 seconds to pick gives you the 5 seconds warning you need.

Of course, there is a very simple reason to use a lock which you are overlooking. Without a lock then anyone who desires to can casually enter through a door, even those not determined or motivated. So a mischievous neighborhood kid could simply walk into my front door and abscond with my laptop, or my kitchen knives, or any of the many valuable portable objects contained in my house. On the other hand, the mere presence of even a commonplace Kwikset lock deters the casual neighborhood thief, or keeps my 5 year old from walking in on me in the bathroom, or keeps drunk college students out of my liquor cabinet.

I'm actually much less worried about the determined, well-prepared thief than the casual opportunist. That thief is much more likely to select my neighbor across the street whose large plasma TV is plainly visible through the window. So I'm somewhat protected by simply being a less desirable target.

This is even more the case with my vehicles. If I left my shiny brand new car parked on the street with the keys in the ignition, doors unlocks, I'd be frankly surprised if it was still there when I got back, because any mischievous teenager who saw it would almost be a fool not to take it. Same for my $400 bicycle: left unattended and unlocked outside of the grocery store, would a homeless man in his right mind not take it out for a ride? My unlocked bike was "stolen" quite a few times from my college campus, and each time I admit it was my own damn fault. On the occasions (two) when my properly locked bike was stolen by a motivated thief at my high school 100 feet from the security guard, I was upset that the guard was not doing his job, but even then, possessing the nicest bike on the rack made me the preferred target of the motivated thief.

Furthermore, my home and car are well-insured, but the coverage under those policies do require that I exercise "reasonable care" in protecting my goods. For that reason, it is prudent for me to possess and use a lock for simple reasons of procedural compliance for financial protection.