Former Nottingham Forest manager Martin O'Neill has hit out at the so-called sacking culture in football.
O'Neill departed the Reds in June following his appointment in January, when he took over from Aitor Karanka.
He took the reins at the City Ground, where he won two European Cups as a player, and guided Forest to a ninth-placed finish with the club harbouring hopes of a play-off spot at the beginning of the season.
The former Leicester City boss was handed a remit of promotion when he signed an 18-month contract with the Reds , but that was terminated amid rumours of player discontent.
O'Neill started life as Forest manager four points off the play-off places but after 19 games in charge - including a damaging run of four-straight defeats in April - saw the club finish eight points adrift of the top six.
"Nowadays you have to have an instant impact otherwise people are saying 'were not so sure about this', O'Neill told the BBC's Test Match Special programme.
"It has to be instant.
"You wouldn't even know the strengths or weaknesses of the first-team.
"You wouldn't know whether there is a good reserve player coming up who might be good enough to play in the team.
"There's no time - but that's the nature of the game."
