I have no trouble writing reviews, even critical ones. But authors who come on here and say things like 'it has been three days and nobody has reviewed my book yet' are, I have to admit it, a bit of a pet peeve of mine. It reminds me of those in the fanfic community who will beg and plead for reviews and then threaten to withhold future chapters if they don't get it
It just says 'total amateur' to me. But ymmv
I think many authors who self-publish ARE amateur---it doesn't mean they aren't potentially writing good books, but I mean in a business sense they are. This should not be undertaken as the instant path to fame and fortune. If they mean this to be a career, they have to look long tail and realize they a) need to put in some serious time and effort and work into promo and b) they need to be patient and pay their dues. Even in the 'old days' it worked that way---Stephen King toiled for years at slave wages as an English teacher while submitting stories to lad magazines. The Eragon kid sold books out of the trunk of his parents car at homeschooling conventions. It takes *time* to build an audience, and if this is your *job* then you have to devote that time. If you don't want to, or are too impatient, or whatever, then maybe this is not the job and career for you and maybe it will just be a nice hobby and whatever you sell, you sell. Certainly, that is a valid lifestyle decision. I myself made it---I just do not have the heart of a business tiger, so I went into a day job I enjoy and whatever writing I do is for fun, on the side.
I just really, really get tired of the 'you downloaded my book, now where is my review?' attitude. People have lives too, and the book may be your baby but to them it's one more thing to get to. Give it time, build up some good will and reputation, and if your book is good, it'll get out there. But don't beg for reviews, seriously. It just makes you look immature.