Ha! Yes, my 1500+ posts are all about disagreeing with people's opinions.
I think the biggest reason some are disappointed is because they are looking for thrills and chills. They want excitement, but they don't know exactly what will give them that feeling they crave. Ask them why they are disappointed, and they say, "I want more." Ask them to define "more" and either they can't, or they rattle off the name of another product. Ask them why they don't simply buy the other product and be happy, and that's about the time they start calling you a sheep, a fanboi, or tell you to stop drinking the koolaid.
The truth is that it's not the product that is lacking.