I always wear a screencover/seal on my phone untill I went to a Smoking Eel party recently (“NK Palingroken“), my phone was so oily that the screencover just slide off.. the screencover was dirty and messed up so I put the phone in my trousers without screen protection.
A few days later I thought the touch screen was broken, the screen itself did work but it didn’t react when touching it. I thought a reset would work.. NOT.. a hard reset.. Still nothing..
I noticed it sometimes react on a touch.. but totally weird.. at the wrong place. Did it un-align in my pocket ?

On HTC devices there is a shortcut to Align the Screen when you can’t use the touch screen:
Press the UP button (mostly the scrollwheel UP) and the Volume-UP button at the same time.
This gives you the “Tab screen to Align” tool.

In my case, the screen didn’t respond and this was not the solution, doing more research, I found the following:
The touch screen exists of several layers (see below), sometimes two of those layers are stuck to each other (can be because it’s getting older or when it’s temperature raises and is under pressure like in a trousers), you can unstuck it by rubbling with your fingers and thumb over the screen.

See this forum post of a man who said he works for Texas Instruments and makes thse screens.