The messy, black smudge that can be seen at the edges of this electrical tape can be removed by wasting more tape.  The assumption with buying this 3M Scotch tape is that performance is the most important virtue and that 3M Scotch brand has experimented with dozens of different adhesives before choosing this adhesive.  Many brands of duct tapes and electrical tapes use inferior adhesives that will disintegrate if left exposed to the sun.