It's generally accepted that music is subjective. Which is to say there is no concrete proof that one musical artist is superior to another and that it's all just a matter if personal taste and opinion. With that said, we do tend to reach consensus on certain things. Some bands are just accepted as being great, while others are widely considered to be terrible. It doesn't mean these opinions become facts, it just means that they start carrying a bit more weight.
One such consensus involves the greatness of The Beatles. Indeed, if you got hundreds of musicians and critics all in a room and asked them who the greatest band to ever walk the earth, The Beatles would take it, and it wouldn't be close.
But are they greatest band of all-time? I mean, is there any objective way we could try to determine that? Well, that's what I'm here for! Let's look at what we know about the Beatles and their legacy, and try to determine if they really are the all-time number one. I should mention form the start the Beatles aren't my personal favorite band, but they are pretty high up there. Still, my personal opinion of their music is only part of the rubric.
First, let's talk about influence. In this category, they're pretty much unparalleled. Just about every modern band was shaped by the Beatles in one way or another. Some bands were influenced by their immense talent for catchy melodies, while others were moved by their ability to try anything. But really, no band has impacted music in the last 40 years more than the Beatles have. Okay, they're looking pretty good so far.
Originality is a no brainer as well. Sure, they were borrowing a bit from 50s rock n roll artists in their early albums, but once 1966 rolled around, they were inventing sounds and genres left and right. When they released "I Should've Known Better" in 1964, they pretty much invented power pop. Three years later, they would play a pivotal role in the creation of psychedelic rock. In general, there was a sense that the Beatles were willing to try anything, and that meant they were the first to try a lot of things.
This would lead into another key category: diversity. On any given record, the Beatles were prone try out 5 or 6 styles of music. They weren't burdened by any notions of what rock or pop was supposed to be, so they integrated anything and everything. From the 1920's pastiche of "Honey Pie," to the aggressive proto-punk of "Everybody's Got Something To Hide Except Me And My Monkey," to the overwhelming sound mashup of "Revolution #9," they were game for anything.
Taking all of this into consideration, there is a damn good case that the Beatles really were the greatest band of all-time. of course, that doesn't make it true. There's still concrete proof that they're better than Radiohead, Neutral Milk Hotel, or hell, even Insane Clown posse. But the career the put together is amazing, and to this day, it remains unmatched.