For riflescopes, I typically make sure no grease/oil on the screws. Many come with some light coating (somewhat like loctite) to help ensure no movement. I don't add blue loctite on the scope rings for my bolt guns. When cleaning, I will typically check the torque on the rings and base. Usually when cleaning the first couple times after mounting, and then here and there after that. I will apply a light coat of oil on the scope base just before mounting (was recommended to me a long time ago).
For the 1-8 I have on my AR, I will check the screws more often as well as put witness marks. Figure the higher rate of fire making it more prone to working/vibrating loose. Haven't had one move, but good to have means of quick verification. I'll typically use blue loctite on most mounting screws on my ARs, except for my1-8 scope though (wasn't recommended by mount manufacturer, so just went with it).
I've read where some apply rosin where the rings touch the scope body. Spuhr mounts recommend it for larger calibers, like magnums. I haven't used it on my .308 or 6.5 cm, but the recoil on those are mild.