Plus 1 on everything he ^^^^ said.

What they said, plus yes, there is a reason to sand between topcoats. At that point you shouldn't be sanding into the stain - just the topcoat. And the purpose of it is to remove slight imperfections in the topcoat's surface and give the next coat a better surface to adhere to. If you want to convince yourself, test this on two pieces of stained wood: don't sand one between coats, and do sand the other between coats. The one that wasn't sanded will likely end up more like it has a thick "wrapper" of topcoat as opposed to a clear smooth coat.

Thanks! I just re-sanded the area back down to the original and started
over with the Gel stain and the Gel Top Coat...still had the same
problem with one section (but was the backside of drawer), but the other
section worked... I had a large bottom cabinet and upper cabinets with
mirror and light frame already stained, so I needed to follow through
and make it work as they say...would not use or recommend these products
to anyone else!!! Gave plenty of dry time in a warm and low humidity room... sanded before applying gel stain and during top coats..but for whatever reason the top coat removed the gel stain... oh well....

I gel stained my kitchen cabinets a couple of months ago. In my research prior to starting I read about this problem. A video that I watched said to spray the stain with shellac prior to applying the top coat.

I'm not a fan of fell stain. Never like the results