90% of my Marriott stays are for work. The vast majority of my work stays are for one or two nights. I rarely ask for an upgrade for a work stay. However, my work stay upgrade percentage is around 75%. About 50% of my work upgrades are to suites. I probably could have more suite upgrades if I asked for them.
My personal stays have around 90% upgrade percentage and the vast majority of these upgrades are to suites. However, I usually ask my Ambassador to intervene.