Those people who fold their hems of their pants over their ankles believe that by doing this they are making their Salaah proper, but by doing this they are making their Salaah Makrooh Tahrimee (undesirable).
According to the Shari’ah to read (perform) Salaah with folded clothes is Makrooh. The following Ahadith are very explicit on this matter.
“I was ordered to prostrate on seven parts and not to fold clothes and not to coil hair.” (Sihah Sittah) “I was ordered not to fold clothes and not to coil hair.” (Bukhari & Muslim) “To fold (gather or lift) clothes for Salaah is Makrooh.” (Quoted in most Kitaabs)
“To fold clothes in Salaah or to lift clothes with both hands from front or back at the time of sajdah with a small action is Makrooh or to enter (Salaah) Salaah with folded clothes is Makrooh.” (Ghoonyha- quoted in Fatawa Razvia)
To read Salaah with folded clothes is Makrooh Tahrimee (necessary to repeat the Salaah) and to read Salaah with pants hanging over the ankle and below the ankle is Makrooh Tanzeehi (not necessary to repeat the Salaah).
It is not necessary to repeat the Salaah as A’la Hadrat, Imam-e-Ahle Sunnat (radi Allahu anhu) has stated in “Fatawa Razvia,” Vol.3: “To leave the pants hanging below the ankle with pride is Haraam and to perform Salaah with this intention is Makrooh Tahrimee, otherwise it is Makrooh Tanzeehi.”