I lock my guns up to avoid a tragedy and to always know where they are. If I leave one out near the sofa where I was sitting when i go to catch a movie(recently saw "Parker" w/Jason Statham), I might leave the weapon out. Of course I have a great alarm and my house, doors, & windows are always secure amongst other things. Basically my safe isn't even for thieves...I don't have enough weapons/valuables. I am just happy to know if some idiot kid fired the weapon it wouldn't be in my home...it would be wherever he lugged the safe.
If someone breaks into my house and steals my gun he is liable for any and all issues that arise from that point on 150%. It isn't my fault. It is my responsibility(in my opinion) to make sure the gun are secured so nobody gets a hold of it whereas an accidental or negligent discharge can take place or some other tragedy. I believe my safe accomplishes this due to an electronic code as the only way to correctly open it. The long guns are stored in a locked case.
"Damn the torpedoes, full speed ahead!" -Admiral Farragut @ Battle of Mobile Bay 05AUG1864