Answer:
looking back, there was a certain sound, certain style of music that came out of the mid, late, fifties, early sixties, that was new then, and growing and changing what teens in that era of time were listening to. When the beatles came along, ok, their accent, their hair, was a great gimmick, above all that, think about this, the sound, the sound that they created, their cover songs of twist and shout, roll over beethoven, long tall sally, compare the original songs, listen to them compared to the way the beatles covered them, there was excitement, and energy in the sound, i don't know what technique george martin used in those days with ancient recording technology, but it worked, the sound was full, with energy, it was a different, different, different sound.
alot of the critics in those days could not have cared less for the hair and the accent, even they knew then, there was something out of the norm for that day and time. grab any original song the beatles covered, listen to each song carefully, even to this day, you will feel the sound, and when you feel what your listening to, you know you really got something different, that's what caused the beatles invasion, after that, everyone was hungry for more with curiosity to see what the next group was going to bring, unless you was 13 to 18 when they came out, your judgment call is of theory and speculation, just like i can only theorize what happened when Elvis came out, i was only 8 years old when Elvis came out, had i been 18 or older, i would have truly understood why they called Elvis, the king, his style was different, his sound was different, the beatles were different, their sound was different,
any objections or different opinions from what i wrote please let me know, gino274@gmail.com, thank you for your time in reading this, gene