My dryer ate my sister-in-law's favorite dress and I couldn't figure out why. After some research, I realized it was the lint trap.
If corners of your lint trap protrude from its slot in the dryer it can catch on fabrics and the rotation of the dryer drum can pull at the fabric until it rips.
The problem doesn't only damage your clothing. When your lint trap doesn't slide all the way into place it can allow lint and other objects to fall into your dryer and the vent hose. This can be a fire hazard and may damage your dryer, at the very least. Thankfully I realized the problem quickly.
How to fix your lint trap snafu
If your lint trap won't side into its slot properly anymore, there are three reasons.
The lint trap is warped. Warping is caused by sliding it into the filter slot a little less than gently. A warped filter can be remedied by buying a replacement from the manufacturer or an appliance repair supply store.
Your filter is dirty. To clean your filter you probably just scoop the lint off of the wire mesh and stick it back into the slot, like most people. The outer edges of the filter can become sticky from fabric softener and dryer sheet residue and can collect lint balls that prevent it from sliding into the slot. Give the filter a wash with warm water and dish soap and make sure to let it dry before you put it back in the dryer.
Something stuck inside the filter slot preventing the filter from sliding all the way into place. If you have toddlers that like to stick things where they don't belong or teens that never clean out their pockets before sticking something in the dryer, this could be your problem.
To give the area a check, unplug the dryer and remove the lint trap. Shine a flashlight down in the hole to see if you can see an obstruction. If your dryer was like mine, there will be much more than just one object lodged in the filter slot. If you can't get your fingers down into the slot to scoop out the object, use a pair of needle-nosed plyers or a hook made from a wire hanger. Once you clear out the debris, the filter should slide in easily.