I ventured into self-publishing by accident really. I intended to release my out-of-print novel to get the work out there, for what it was worth. This was in 2009. At the time of its release, I discovered Kindle publishing (the only game in town, at that time). When Nook became available, I hopped onto that, too.
The volume of sales my book had at $0.99 turned out to be much higher than I could get when I priced the book higher. So even though I was earning a lower royalty rate, the volume of sales was so much higher, I was actually making more money.