Short answers, pulled from the story.
Producer George Martin had been unhappy with Pete Best's drumming on the first take and remained dissatisfied with Ringo Starr's drumming on the second. On the 11th of September 1962, Ron Richards, Martin's assistant, hired White, a professional session drummer he had used before, to record the song a third time.
White was paid £5 for the session itself and 10 shillings for bringing his own drum kit. He did not receive any royalties from sales of the records.
White's version features tambourine throughout, because Ringo Starr was relegated to playing tambourine during that session. Starr's own version has no tambourine.
Recorded on the 6th of June 1962, the Pete Best version was initially thought to be lost. It was released for the first time on the Anthology 1 compilation in 1995.
He went on to play on hit records by Herman's Hermits, Tom Jones, and Lulu, toured with Marlene Dietrich under Burt Bacharach's musical direction, and worked with Rod Stewart and Anthony Newley among others. In the late 1980s he moved to Caldwell, New Jersey, where he taught pipe band drumming and later recorded again with the Smithereens in 2008.