Graeme Swann: England spinner 'powerless' in Ashes series
Graeme Swann said he chose to walk away during England's Ashes whitewash because his bowling was "awful" and he felt "powerless" during matches.
The spinner, 34, who quit cricket after the third Test, described the decision as the "most sobering" of his life.
"It was a horrible feeling to come to terms with," Swann told Radio 5 live.
Swann also gave his backing to captain Alastair Cook, saying not even legendary skipper Mike Brearley could have turned around a failing team.
England's sixth highest Test wicket-taker with 255, caused a major shock when he announced his retirement from all forms of cricket four days before the fourth Ashes Test in Melbourne.
Speaking on 5 live's Not Just Cricket, which airs at 21:00 GMT on Monday, Swann said his performances in the first three Tests - he took seven wickets at an average of 80 - caused him to bring forward a departure he had planned for the end of the tour.
As the effects of a second elbow operation in March 2013 took their toll on his bowling, the one-time match-winner, who made his Test debut against India in December 2008, felt he had become a liability.
"Quite simply, I was awful," he said. "Whenever I bowled in the past, I could always get a lot of revolutions on the ball, dip and trouble most batsmen I bowled at.
"But from the outset of the tour, in the warm-up matches, I just couldn't do it. After my second elbow operation, I've never really got the same revolutions I got before it, but it just [deteriorated] and I really felt powerless to tie people down.
"In Adelaide, I was getting hit for six by a rabbit who bats at number 11. It gets to a point that you realise you are hindering the team. You are not helping them in any way.
"It's a horrible feeling to come to terms with because you are playing for your country, you love playing cricket for England and it's your life, but to actually come to that conclusion is possibly the most sobering decision I have ever had to make.
"It was horrendous."
The 5-0 whitewash in Australia was only the third in England's history and statistically their worst ever Ashes tour.
But Swann was quick to deflect criticism from Cook and described the dismal series as a collective failure.
"No man could have captained us this winter - there is not a captain on earth," he said. "You could bring back Mike Brearley and he wouldn't have done any good.
"We were terrible. We have got to get more improved performances from the team and then the captain will be able to do his job.
"Cook should keep doing the job he was doing beforehand, not panic about what has happened and just get everyone together and think how are we going to go about scoring big runs again.
"That is the only way you can win Test matches. It's what we did arguably for five years. We were so good because we had such a reliable top order who were scoring so many runs. If we can get back to that we will be fine."
The aftermath to England's disastrous Ashes campaign has featured claims of splits in the dressing-room.
Swann says the reports, including a rumoured rift between coach Andy Flower and star batsman Kevin Pietersen, have been wide of the mark.
"It will probably surprise people to hear that the changing-room was not divided," he added. "It was remarkably calm. People just knew we were not performing and they were doing whatever they could to improve that.
"Some of the stuff I have read is just a made-up pack of lies. There was one line in one of the famous tabloids saying KP refused to go to the Christmas dinner. He sat on the table next to me with his whole family.
"He's had his moments in the past where he certainly has been divisive in the dressing-room, but to be fair to Kev, since coming back from his 'reintegration' he has been much improved."