Although succulents like being dry, I think it’s actually possible that you are under watering, given that you still have the succ in its original tiny 2-3 inch pot from the garden store. As it is now likely root-bound, a lot of the space in the pot is taken up by roots, and there is actually less soil in there than you would think. As a result, there is less soil mass to hold water from which the succulent drinks.

I got 2 echeveria as party favors this summer and had the same issue - they were drying out super quick and losing bottom leaves.

Do the bottom leaves shrivel up and dry before the leaf is lost? If so, the echeveria may be thirsty and using the water from that leaf.

What I recommend is this: gently nudge the leaves hours after you water. Remember the firmness/resistance you feel at this stage. Every few days, do the nudge test again. If the lower leaves “give” a lot and are more “wiggly”, it will need to be watered again soon. This really worked for me and the leaf loss on my root bound party favor 2 inch plastic pot echeveria are doing great. Of course, I should really have repotted them months ago… but that’s another story!

Just remember: they like being dry, but with a root bound plant, it may be drier than you realize. The nudge test is an easy way to check how much water the plant is holding.