Larry from U2 said: I thought it was a great idea to get someone to come in to help us develop in a different way. It seemed we had done very well on three chords and the truth but we needed someone who could take our songs in a different direction, add new textures and explore new ways of using the studio.

--- I think these words come from one of their songs "All I have is a red guitar, three chords and the truth". It seems to me that "three chords and the truth" mean that they play simple things which consist only of 3 chords and sing about the truth. So, Larry says that they were pretty good at playing simple things and talking about the truth in their songs, but needed something more. That's my interpretation. What do you think?
"Learned' " musicians often put down the purveyors of early rock and country by saying "they only know three chords." It goes back as far as I can remember - country before rock.
Yes, that's exactly how I understand it.
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