I liken it all to Entertainment.
Some evidence is interesting, some of it not.
If you have ever encountered spiritual activity, it's very random at best.
I live in New Hampshire, not far from a river where back in the day a lot of Indian wars took place. I am fairly confident that there are spirits on
my land, if not in my house.
My Dogs watch them all of the time which is how I know that they are nearby.
I once had installed new high power headlights in my Jeep and was taking before and after pictures at night only to find, misty fog like forms in all
of my photos.
I was going to bed recently and at the top of my stairway saw a glowing golfball sized orb (not dust) darting by. Its unexplained phenomena. I
haven't any proof as to if it having occurred or not.
These don't occur every day and are sporadic at best.
Thats why I believe that not every show can or will find evidence.
That is also why I generally record these shows on my DVR and watch them later on.
A few interesting programs that I recall:
On Ghost Hunters - the IR camera capture of the the guy in the basement wearing the Union soldier hat was pretty interesting, as well as being fairly
difficult to fake.
Whereas many of the EVPs are interesting as well.
Ghost Adventures did capture a form walking from left to right in one of their episodes out west which was pretty cool.
You could distinctly see the misty outline of the individual.
That was pretty good evidence.
Most Haunted :
Does have the annoying shrieking women who are scared of their own shadows but they also have the skeptic Doctor investigator who critiques the
evidence discovered during the episode at the end of the program which I feel is honest and exemplary in weeding out the theatrics.
All in all , I am a believer in the paranormal.
But in all consideration of probability and statistics, as well as my own experiences, They are not necessarily going to show up on Que for every TV
Your mileage may vary.