It could be happening right now, while you're safely at your desk or on your couch. It happens quietly, when your guard is down. Some say it is magical, others say...demonic. What am I talking about? Migrating tools! They are stealthy, these wrenches, drills and rivet guns. You place them in your toolbox, right where they belong - and the next thing you know - there they are, right back out in the open. The phenomena is unexplained, very much like the fact that a box of clecos placed in a closet will slowly disappear... but the population of coat hangers will increase... coincidence? I think not!
I notice the great tool migration most shortly after I have finished up a project, cleaned up the shop, and put put everything away. Then a new project comes along. You need a wrench at the job site, then another - then the right sized one (the wrong sized ones stay out, because you know you'll need them later). Then a pair of dikes to cut the safety wire. Needle-nosed pliers to pull a cotter pin... and the screwdriver to pry the end of the cotter pin up. Each tool requires a trip to the tool box of course - this is your tool's way of utilizing you as transportation. Before you know it, half of all your tools are partying at the job site, wrenches scattered about the floor, clecos rolling around the cockpit. Drill bits are scattered about because you needed a #40 to pilot drill, enlarged to a #30, then a #19 for a #8 screw - and don't forget the #10 to open up for a nut plate... and oh , yeah, you're going to need that #40 again for the nut plate rivet holes... better just keep them all out!
What will help you to tame the migration is a cart of course. It does you no good as the tools come out, as they do that one by one. But keep a roll-around cart handy and place them all on that when you're done... and the tools get a free ride back to storage, to be sorted back into their beds; tucked away until the next project.. until the next migration begins!