I play Mid most consistently, but I'll sometimes I'll just change roles on a whim and spam a different one (except jg. ew.) for like a week. I like playing mid because I feel like the champs there have the most interesting and influential kits and I actually feel like I'm doing something every time I Asol E down to botlane as opposed to sitting on some adc farming and knowing I'll eventually be useful. In addition, many of the mids just have an odd appeal to me that makes me just wanna play them even if they're in a bad because they're, for some inexplicable reason, most fun to me.
Alternatively, I'll usually play support because the idea of invisible power and giving agency to others above myself appeals to me (usually a supportive player in games like Battlefield as well). Also, the support class is imo the most diverse in League which gives a bunch of fun and different lane phases depending on the picks. Unfortunately, since the current state of support is "pick a mage and kill the other laner", I'm kinda turned off by the role atm.
I'll occasionally change these roles just 'cause I'll get a random craving for a random champ (Sivir was a recent one) where I'll just have the time of my life playing them until I get burnt out like 10 or 20 games later. Probably would consider switching to playing top more often since a lot of the principles that I enjoy apply to tanks as well, but I'm not comfortable enough holding the team's tp yet.