I've Googled it and stuff... but I don't get a straight forward answer.
Most Helpful Guy
Hair grows in cycles, only about a quarter or so of follicles are active at any one time. So any removal process that claims to be permanent can only act on the follicles that are active, which would leave at least 3 more treatments. But like most biological processes, it's not a perfect cycle, so some will lay dormant longer than others, which is why you'll rarely get 'perfect' permanent results, though some do get fairly close. And the body tries to heal the damage it gets, which also can result in small amounts of regrowth.
Waxing is not permanent at all, but is cheap, widely available, and requires minimal training for good results. Most people gain a tolerance to the pain in time. Most common side effect seems to be ingrown hairs.
Laser is claims permanency, but also requires a skilled (and best to be licensed) operator. The laser automatically searches out contrast (where hair meets skin), and zaps those areas. Costs are moderate and treatments aren't too long, either. There is some risk of discolouration, but mostly this is caused by sun damage after treatment (or sun-weakened skin before treatment).
Electrolysis is generally regarded as the best for permanence, but is also has the highest costs and pain associated with it. It also takes longer because it is a single needle inserted into each follicle individually. There are few risks associated except for lots of pain and a lightness of the pocketbook.0