Interview Questions

As a person who was unemployed (or out of work, between jobs, freelancing--take your pick!) for what seemed like a very long time, I am always fascinated by the whole job search (and rescue?) process.
 
I have, over the years, been ignored by job posters and Facebook job networking groups, and I have, quite often, evaporated into the ether of online application forms. I have been on interviews that went so quickly that if they started early, they ended before their scheduled start times. I have waited on things that sounded promising, but never came to pass.
 
I have also been hired sight unseen from a networking site, hired through just emails by a person who "heard about me," and hired to "start tomorrow" on a job I knew little about except that a friend referred me.
 
On the flip side, I have watched friends of mine go through multiple many-hour interviews for each job that comes up. Hours upon hours of their time are spent preparing and rehearsing, not to mention getting to and from the location many times and talking for hours to teams and leaders and everyone (it seems) who might possibly have contact with them should they get the job. I don't think they necessarily get the jobs any more often than I do. They just walk down a longer path to the disappointment.
 
So, how can it be that the process is so different in their world and in mine? Perhaps it's that in my field, since most jobs are freelance, there's no obligation to find the exact "right" person. The person might be in the job for such a short time that it doesn't matter, and, being freelance, could be cut loose on Day 2, no questions asked, if things aren't working out. And if the person knows how to do the work or operate the equipment, does that person's overall knowledge of the field or work ethic really matter?
 
As I talk to friends who have had to go the long interview route, I can't help but wonder--do you really get to know someone better by putting her/him through a marathon series of interviews? Is the time spent really time that makes a difference when hiring choices are made? I may wonder sometimes about what can seem arbitrary in my field, but it's hard for me to watch friends jump through hoops, over and over, only to have to do so again when long interview processes produce no results.
 
I am not, and may never be, a hiring manager (unless you count my hiring of babysitters over the years), and I am sure that there are ins and outs I don't know. (And, for the record, I happen to think that work ethic does matter, even on a short-term freelance job.)

My question is--if job searching is hard regardless, why are we making it even harder?