Not Secure

Nothing stored in your car is secured.

Nothing.

Not even that lock box bolted to the floor.

I'm mechanically inclined and I've spent a lot of time taking cars apart (sometimes even getting them back together).

I've astonished more than one friend with the speed with which I removed their old stereo to facilitate the installation of a new one.  "And I didn't even break anything taking it out!" I'd reply.

Car security is a filtering mechanism.

You hide things out of sight so that a thief doesn't see something worth breaking the glass.

You lock the doors so the thief has to risk breaking the glass.

You bolt a lock-box to the floor of the trunk so that it takes more time for the thief to steal what's in it.

You hope that the thief doesn't have a means to bypass your locks.  You hope they don't have tools to breach your lock-box.  Hope.

Would you be surprised to learn that when your car got burglarized it was probably the thief's second or even third visit?

The victim is a participant in the victim selection process.  The victim is not a participant in the crime.

The first visit is to determine if you're someone worth stealing from.

Subsequent visits are to see if you've made a mistake or plain let your guard down.  They only have to get lucky once, you have to be lucky every time.

Sooner or later you're going to experience a loss.  Count on it.