My grandma has been doing this for years. Mom just started needing to wear diapers and she's doing the same in the bathroom right this second. Soiled or new, they both will sit there and meticulous rip the absorbent pad off the diaper. WHY!!!!!!!! On every diaper I've tried, the absorbent pad is just glued on a disposable underpant. Are there any diapers where the pad is more integral to the underpant so that it can't be torn off?
I will take this as a notice for future events.
Unfortunately, just like a toddler, they cannot tell you why they are doing it - but I often wonder if the underlying reason is discomfort. If you're using a name-brand, try the store brand.. If you're using a store-brand, try using a name brand. Also, just like baby diapers, some are better for boys and some are better for girls.
You might consider starting a thread with "What 'Diaper' are you using for your senior and what sex is this senior?" This will give you a better handle on "are any better than others?"
I don't have my DH in them - I have a urinal on his walker instead. Diapers cause UTI's and Fungal Infections - I'd rather just use the urinal with him as long as possible. Again, just like a toddler, as long as he has to hold it, he seems to be able to hold it - and he's 96.
As for trying different diapers, the storage room is like a diaper stockroom with various types of diapers with only 1 or 2 having been used. So far the best for diaper ripping out prevention is a XL child's diaper. They can't rip the pad out of that but the achilles' heel is the sides. They rip far too easy and thus they just pop off many times when they are just pulling them back up. Since those have been the best so far, I'm considering sewing up the sides to deal with it.
The ones I'm most disappointed with are the ones advertised as "slim" and "discrete" and being "just like regular underwear". I'm not seeing it. They are the same as any other diaper. A problem is getting diapers that are small enough. Both my mom and grandma are well under 125 pounds. "Small" adult diapers are for women up to 190 pounds. XL "child" diapers are up to 125 pounds. I think it says a lot about the obesity problem in the US that "small" adult women are 190 pounds and a child that still need diapers is 125.