Why are tarps so much longer than the rigged length of hammocks? Hammock ridgelines(RL) are often just over 100", under 8.5 feet. Full sized tarps are at least 120"/10' and often are longer.

A little extra coverage is good, but why so much extra? It appears that the tarp makers look at the fabric length of the hammock, not the rigged length.

I'm not seeing one person tarps for ground use that are 11'/132" long.