In a 1968 interview, McCartney said that the song was "about the hole in the road where the rain gets in, a good old analogy—the hole in your make-up which lets the rain in and stops your mind from going where it will." He went on to say that the following lines were about fans who hung around outside his home day and night, and whose actions he found off-putting:

See the people standing there
who disagree, and never win
And wonder why they don't get in my door

The first of two recording sessions for the song was at Regent Sound Studio in London on 9 February 1967 in three takes. Regent was used because EMI's Abbey Road studios were not available that night. This was the first time that the Beatles used a British studio other than Abbey Road for an EMI recording.Overdubs were recorded on 21 Feb 1967 at EMI studios Abbey Road.

The lead vocal was recorded at the same time as the rhythm track, a change from their post-1964 approach of overdubbing the vocal.

Paul has also stated about the recording: "The funny thing about that was the night when we were going to record it, at Regent Sound Studios at Tottenham Court Road, I brought a guy who was Jesus. A guy arrived at my front gate and I said, ‘Yes? Hello’ because I always used to answer it to everyone. If they were boring I would say, ‘Sorry, no,’ and they generally went away. This guy said, ‘I’m Jesus Christ.’ I said, ‘Oop,’ slightly shocked. I said, ‘Well, you’d better come in then.’ I thought, Well, it probably isn’t. But if he is, I’m not going to be the one to turn him away. So I gave him a cup of tea and we just chatted and I asked, ‘Why do you think you are Jesus?’ There were a lot of casualties about then. We used to get a lot of people who were maybe insecure or going through emotional breakdowns or whatever. So I said, ‘I’ve got to go to a session but if you promise to be very quiet and just sit in a corner, you can come.’ So he did, he came to the session and he did sit very quietly and I never saw him after that. I introduced him to the guys. They said, ‘Who’s this?’ I said, ‘He’s Jesus Christ.’ We had a bit of a giggle over that…But that was it. Last we ever saw of Jesus!"

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Wikipedia