I want to be clear, I've picked up this hobby as it intrigues me, not because I have criminal intent.
In my day job I work securing computer networks and their attached devices. IT security is a carefully built house of cards, and while there is much you can do to harden a system it doesn't take much for it to crumble. I've also found that often people put more trust in their digital security practices than they should. This isn't to say you can't be secure, you just have to understand what it is securing you, how exactly it works, and how to properly use it.
Physical security is no different. I'm intrigued to understand those intricacies and there is no better way of learning how something works than to understand how to defeat it. This ability to manipulate and non-destructively open many locks and security devices which are in common use is what I like focusing on.