When some men takes a dump a small portion of the excretion is hung up in the rectum when the external sphincter ani muscles pinch off the delivery. It will remain there no matter how much pushing or wiping is done. It will only be dislodged and delivered through the rectum after a few good farts. A tickturd is the source of most skid marks in a mans underware.
Honey, its those damn tickturds that leave the skid marks!