Full Manual Turntable-What to do

I've really never understood from a vinyl lover's perspective and from a logical standpoint why those that choose to leave the motor on between lp changes, do so.

If the main argument is saving the motor /switch vs. saving your vinyl?.. I'll always go for saving my vinyl.

If the main argument is being "cool", I'd rather save my vinyl.

If the argument is one less "step" in the playback of vinyl, I'd recommend those that adopt that option to quickly get out of vinyl reproduction.

To the Op's reasoning, Is the TT motor more important that the vinyl? I think you came to the appropriate conclusion.

If the main argument is saving the motor /switch vs. saving your vinyl?

Neither, the argument for leaving the motor on is that the vast majority of motors take a long time to fully speed stabilize and hence you are best of to avoid turning them off if you can avoid it. Provided your mat is not "sticky" then there’s no real risk to the disc in taking it off a moving surface. In the case of my deck where the platter is coupled via magnets to the motor I can stop the platter while leaving the motor running so I tend to leave it on

One of the beauties of direct-drive or idler-drive is that the platter gets up to speed much more quickly than does that of a belt-drive turntable. In that case, the choice for me is clearer; I shut the motor down not only between LPs but also when flipping the LP in play.  On a practical level, the sluggish start-up of most belt-drive turntables is partly what drove me to experiment with other drive systems.  Still, no matter what type of turntable I have owned, I shut the motor down between sides.  But as others have said, there is no "right" or "wrong" on this issue, IMO.

If you feel the need for the motor to fully "speed stabilize" , then by all means, take this route... any user imposed faults to your prized vinyl, well, that's on you.

(By the way, I concur that it does take a while for the speed to fully stabilize.)
This isn't enough of a concern for me in order to make any adjustment in my normal routine that takes into consideration, ("Vinyl First").

I can always visualize any removal of a vinyl record from a spinning platter...if not done (precisely) will always be a negative. I can think of no other situation in which this action can be a positive. Therefore, regarding preserving your vinyl, how can anyone confidently say, this would be of no negative consequence for a vinyl record? To do so, would go against any sort of logical reasoning!

I think folkfreak's situation may be not "the norm" of most of us here.

I agree with all those who have suggested not changing records or sides while the platter is spinning. 

What I've never understood, though, is why so few people seem to use a record clamp (as I do), which of course would make the question moot.  Having a record coupled to the platter only by virtue of loosely resting on it, and perhaps also via some unknown amount of pressure between it and the spindle, just doesn't seem to make a great deal of sense to me.

Regards,
-- Al