What are some disadvantages of alpaca wool?

Alpaca wool is very time consuming to both get off the animal and to turn into something useable. It can be very difficult to use as a medium in certain places because of the lack of need/practicality. 

How long did it take you to write all that out? ?

Generally spontaneous human combustion is something that still bewilders some, human combustion happens very rarely and doesn't affect the surrounding areas, so unless you want to set your self on fire, human combustion will remain spontaneous and very rare.