(A few of the purported 620 bands playing and working in the Liverpool vicinity between 1960 and 1965)
Somebody once remarked that The Beatles didn't create Merseybeat, Merseybeat created The Beatles. Judging from how far back the phenomenon goes, I would say that was probably true. And judging from the number of bands there were claiming the genre Merseybeat, I would say it was a rather crowded little niche.
Around 1980 (I don't have the exact date), BBC Merseyside (the local BBC outlet) broadcast a documentary on The Unreleased Merseybeat, which offered some up fascinating (and in some cases not at all surprising) examples of the bands and the music that got left on the shelf or on tapes in someones basement of some of the bands performing around there from the very early to mid 1960's.
The history of Pop music is dotted with hundreds if not thousands of examples of musicians whose contributions were either ignored, forgotten about or who simply never made it out of the starting gate. Some of it is justified, but in most cases a lot of it isn't.
And it just goes to show you how much of a crapshoot Pop Culture truly is.