I trained my girls to use the disposable potty pads and things were fine other than them shredding the pads...so...I took the advice of some here on YT and switched to the washable potty pads. At the time it made sense...they couldn't shred them...it saved money...yada, yada, yada...
However, now my girls will pee on my throw rugs at times...I think it's because the washable pads are soft and cushy like a rug. I wish I would have found the disposable pad tray and stayed with the disposable pads in the beginning. I now use the tray with a disposable pad and things are back to normal.