There are two basic methods for hair removal- either you cut hair down or you pull hair up out from its roots. Laser treatments and electrolysis work a little bit differently (as they are permanent treatments and not temporary treatments) but overall every hair removal method uses one of those two principles. Epilators are pulling devices, which means that when you remove hair with one of them it's going to be gone for at least 3 weeks and for as many as 8 weeks, and that when your hair comes back it will eventually start coming back softer and lighter than it used to be. This right off the bat makes pulling betting than cutting when it comes to hair removal.
The reason most people don't use pulling methods is the fact that they can be inconvenient or expensive. Sugaring & waxing work best when performed by a high-end professional and tweezing & threading re only really viable when it comes to removing eyebrow hair and small amounts of lip or chin hair. Perhaps the best point that epilators have over all other hair removal methods is the fact that they provide the effectiveness of large-scale pulling methods with the convenience of being able to do it yourself at home.
Epilators can be fairly expensive compared to a razor or no no hair removal reviews products or even an at-home waxing kit, but you only ever need to buy one. Think of your epilator more as an investment than anything else and you'll realize that its single initial cost will save you money in the long run.
The only other negative point of using an epilator is the fact that it takes more time than waxing or shaving. Epilating doesn't take a particularly long amount of time but it takes more than a couple minutes to complete and it can take awhile when you're first getting used to the machine or have an especially large amount of hair to deal with. Finally epilators do hurt to use but the pain they cause is more like the pain caused by tweezers than the pain caused by pulling off a big strip of wax.
Epilators aren't perfect but they do provide one of the best, if not the best, combinations of effectiveness, convenience and price that the hair removal market has to offer these days. They are worth at least a quick look though most people who try them out are quickly converted to what they have to offer. Over the next few years expect a big boom in popularity for epilators.