Richards says Ramdin needs to develop a killer instinct, a lack of which he believes has worked against the home team throughout the Test series. England lead the series 1-0 after drawing the first Test in Antigua and winning the second in Grenada by nine wickets, reports CMC.
"There are times when he is positive and there are times when, sometimes, where the falling asleep syndrome sort of comes into play. You can see from the outside; when England were 40 something for three, there could have been some much more aggressive attitude in terms of getting (Joe) Root and (Ian) Bell out," said Richards.
West Indies have been heavily criticised for surrendering a position of strength and crashing to defeat in the second Test by losing their last eight second innings wickets for 105 runs.
Richards, who as captain won 27 and lost eight in 50 Tests, says there was no reason for the Caribbean side to lose the game.
"One has got to remember also that if you cannot win the match you should not lose. It wasn't a devil as a wicket, but we still got out and especially from good positions," said Richards, regarded as one of the greatest batsmen of all times.
"It's all about playing as hard as you can knowing you are behind and the only thing you have left now is basically for you to try and draw the series. We haven't totally been outplayed, so at least there is a chance."
The third and final Test starts on Friday in Barbados.