Before the Beatles music was mostly done by professionals who were trained to be musicians. There were songwriters and there were performers, but they were trusted “experts”. The songwriters wrote songs that were outwardly expressive, but, not introspective at all. The Beatles came along and with little to no experience, broke the mold and allowed anybody sitting in their bedrooms the inspiration and motivation to start bands and write songs about their own experiences and emotions.
The music varied in style and topic and all of a sudden, there was a musical revolution.
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