I find it interesting how people get DOMS in different muscle groups even when performing the same movements. For example any kind of bench pressing - flat, incline, DB etc. my delts get sore, never my chest. However, dips performed at any angle, usually make my chest sore.
I find the further into a program I am, the less DOMS occurs. Usually I get it when I try something different, like a new movement or very high rep sets.
But I think every dedicated lifter has to at some point experience the savage pain of a highly intense squat workout, where you must stop before every flight of stairs and ask yourself: "Is it really that necessary for me to go up these stairs? Surely there is another way?".