Creator Backlash: Bjorn and Benny aren't too fond of "Santa Rosa", "I Saw It In The Mirror", "Ah Vilka Tider", "Dum Dum Diddle", "Summer Night City" or "You Owe Me One". They also don't like parts of "Just A Notion" and "Just Like That" hence editing them for the ABBA Undeleted Medley. Also, they disliked the chorus of the song "Terra Del Fuego" so much that they edited it out and renamed it "Here Comes Rubie Jamie" for its part of the Undeleted Medley.
Bjorn and Benny have been critical of some of Abba's poppier moments. Regarding "You Owe Me One", they did not include it on the 2001 reissue of The Visitors even though it was on the 1997 one. However it was included on the Deluxe Edition.
Benny said that he found the hard rock experiment "Watch Out" somewhat embarrassing in hindsight, and that it could easily be removed from his and Bjorn's track record without anyone noticing. The song is quite well regarded amongst fans though.
They also were pretty upset with how badly "So Long" did in the charts considering they rated it as being a good song and a guaranteed hit due to its intentional similarity to "Waterloo". They realised that writing to a successful formula was not always the way to have a hit, although they did find one later when they started writing lyrics about failing relationships.
Old Shame: Benny and Bjorn have expressed embarrassment at their first album, Ring Ring, and some of the stuff on Waterloo.
When Abba began getting popular again in the 90s, Bjorn and Benny were bemused by it, feeling that their music was dated and they had moved on from that period of their lives. That's not to say they weren't flattered by their continued popularity, and they did work on archival releases because of it.
What Could Have Been: ABBA didn't intend to split permanently in 1983 (hence why their compilation album was called "The Singles: the FIRST Ten Years") Rather, the intention was to go on hiatus for a year or two, during which time Bjorn and Benny would write the musical "Chess" whilst Agnetha and Frida would focus on solo careers. However, for various reasons they never got back together. When you look at how the band evolved over their decade-long lifespan, it would have been very interesting to see what other songs they might have recorded had they lasted a few more years...
The song "Arrival" was supposed to have lyrics but Bjorn forgot to bring them to the recording sessions. The lyrics were about the birth of his and Agnetha's daughter Linda.
It's speculated that the hiatus made them realise they didn't like working with each other anymore.