Well sometimes I think there are individuals who "sound authoritative and professional;" heck even Wikipedia tends to sound authoritative and professional but it's an admitted fact that it's flawed, based on an honor system (no degree required to edit Wikipedia) and can't be counted as conclusive without research into its sources. People have a tendency to read something and feel like, "Wow that's impressive, this guy sounds like he really knows what he's talking about and has done his homework." Extensive knowledge is required to really make a good assessment of an author.
We have been conditioned to trust authority figures. Just today I had a bad experience at a very impressive dentist's office where I got the worst verdict of my life after the best brushing I've ever done. It was uncomfortable and disconcerting to have to say, "I think this very professional-seeming dentist has used the word 'decay' just so he could replace my silver fillings. I need a second opinion." Psychologically, my mind resisted the idea of questioning a guy with degrees when I don't have degrees (let alone in that field). I had to use common sense to determine that the pattern didn't track, and I felt like I was being irresponsible. It helped that I had my "hinge lady" with me and that she agreed with my suspicions.
It's like the archtypical car shop where you need one little part replaced and the mechanic says, "Oh you're lucky you came to me soon enough. We have to fix this and this and this and sure it will cost you thousands of dollars, but we'll be saving your whole car, just in time."
Ah, for the good old days when I didn't realize I needed to be paranoid.