real physicists (not string-crap) have to deal with real phenomena, which are always hidden behind a lot of noise and interference. there'll be all sorts of things going on, that you don't want to measure, and they get their way into the detector. so you have to be able to extract the real signal, and study its "physics". you learn to get into the bottom of things, and be patient and careful. there's a lot of intuition behind the physicists work, but it's an acquired skill. it comes with experience, and helps to navigate through complexity of a real world phenomena. it's what distinguished physicist from mathematician trying to do something in physics, they lack that heuristic without which you're lost. also, many physicists are superb engineers, because they have to build their instruments and design experiments. it's non-trivial task, because of all the interferences which i mentioned. even theor physicists have to be engineers at times if they participate in any kind of experiment design, and most of them do. there are some physicists who don't care about the real world connection though, i won't mention them here, they don't deserve it.