Scholes, 35, won the last of his 66 England caps six years ago and rejected an approach by Capello last month.
GEAR:England WC clothing range
"It's a big decision and I wasn't really given enough time to think about it, so I decided not to take up the offer," Scholes told the Oldham Evening Chronicle newspaper.
"If they'd asked me earlier, I probably would have accepted."
Liverpool defender Jamie Carragher, who announced his international retirement in frustration three years ago, was persuaded by Capello to return and is part of England's World Cup squad in South Africa.
But Scholes would not have been happy with that.
"There are players in the squad who have spent nearly two years flying all around the world helping England qualify for the World Cup, whereas I haven't been involved for a long time," he said.
"It wasn't a case of wanting to go on holiday, it was the fact that I got the call so close to the tournament and also I didn't want to take the place of someone who helped get England to South Africa.
"The idea just didn't sit comfortably with me," said the veteran of the 1998 and 2002 World Cups.
The month-long World Cup kicks off on June 11.
'Obviously Messi is the best player in history and being compared to him means that you're doing things right, but I try to be myself': Barcelona star responds to comparisons with Argentine legend
'Darwin Nunez would be gold for Arsenal': Liverpool legend claims Gunners should have signed Uruguayan striker in January
