Thanks to all for your interest. Further to what Nick mentions, Wiki's page on Pete Best says it quite well, I think:
Best has never been told why he was dismissed from The Beatles, as the only reason Epstein gave was, "The lads don't want you in the group anymore". It has been documented (notably in Cynthia Lennon's book John) that while Lennon, McCartney, and Harrison usually spent their offstage time together in Hamburg and Liverpool, writing songs or socializing, Best generally went off alone. This left Best on the outside, as he was not privy to many of the group's experiences, references, and in-jokes.
On their first trip to Hamburg, The Beatles realized that the stage suits they wore could not stand up to the hours of sweating and jumping about on stage every night, so they all bought leather jackets, jeans and cowboy boots, which were much tougher. Best preferred to play in short sleeves, so did not follow the style of the group, even though he was later photographed wearing a leather jacket and jeans. Lennon, McCartney, Harrison, and Sutcliffe were introduced to drugs in Hamburg. As they had to play for hours every night, they often took Preludin to keep themselves awake, which were given to them by German customers or by Astrid Kirchherr, whose mother bought them. Lennon would often take four or five, but Best always refused to join in.
Kirchherr asked The Beatles if they would mind letting her take photographs of them in a photo session, which impressed them, as other groups only had snapshots that were taken by friends. The next morning Kirchherr took photographs in a municipal park called "der Dom" which was close to the Reeperbahn, and in the afternoon she took them all"minus Best who decided not to go"to her mother's house in Altona. Best was described by Dot Rhone"McCartney's girlfriend at the time, who later visited Hamburg"as being very quiet, and never taking part in conversations with the group.
Best's popularity with fans was a source of friction, as many female fans considered Best to be the band's best-looking member. It has been said that Epstein became exasperated with Best's refusal to adopt the mop-top-style Beatle haircut as part of their unified look, although Best later claimed that he was never asked to change his hairstyle. In a 1995 BBC Radio Merseyside interview, Kirchherr explained: "My boyfriend, Klaus Voorman, had this hairstyle, and Stuart [Sutcliffe] liked it very, very much. He was the first one who really got the nerve to get the Brylcreem out of his hair, and asking me to cut his hair for him. Pete Best has really curly hair, and it wouldn't work."
Radio Merseyside presenter, Spencer Leigh, wrote a book chronicling Best's firing, suggesting that the other members, McCartney in particular, were jealous. During the Teenagers' Turn showcase in Manchester, Lennon, McCartney and Harrison walked on stage to applause, but when Best walked on, the girls screamed. Best was surrounded at the stage door afterwards by attentive females while the other members were ignored after signing a few autographs. McCartney's father, Jim McCartney, was present at the time and admonished Best by saying: "Why did you have to attract all the attention? Why didn't you call the other lads back? I think that was very selfish of you". McCartney's father later encountered the dismissed Best in The Cavern Club when a Beatles' gig was being recorded for the ITV series Know the North, and said: "Great, isn't it? They're on TV!" Observers reported that Best said nothing, and quietly left. Martin was shocked that Epstein had sacked Best: "He seemed to be the most salable commodity as far as looks went. It was a surprise when I learned that they had dropped Pete. The drums were important to me for a record, but they didn’t matter much otherwise. Fans don’t pay particular attention to the quality of the drumming". Martin used session musician Andy White on the third session for "Love Me Do" on 11 September, and not Starr, who was Best's replacement.
Though sometimes overshadowed by the "handsome debate", musically Best appears to have had a limited rhythmic vocabulary that was seen as holding the other three band members back from their collective musical growth. As stated in Bob Spitz's 2005 biography, "All Pete could do was play 'Fours'..." a style of drumming that uses kick drum notes on every quarter note to hold down the beat. Spitz's book also contains engineer Ron Richards' account of his failed attempts to teach Best somewhat more complicated beats for different songs. On January 14, 2009, McCartney was interviewed on The Howard Stern Show. Stern asked McCartney if Best was asked to leave because Best was too handsome. McCartney replied no, and explained how he, Harrison and Lennon were impressed with Starr's drumming.
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