#6 Colin Todd

Colin Todd, a center-back in his playing days, won two First Division titles with Derby County, the same club which he would go on to manage for just three months, before being sacked after a disappointing win percentage of 23.53%.
Though he helped Bolton Wanderers earn a promotion to the Premier League earlier in his managerial career, he was out of luck during his spells with The Rams and saw himself out of the Pride Park Stadium without making much of a difference.
One interesting thing about his career is that, he's the only manager in EPL with the first name as Colin.
#5 Terry Connor

Wolverhampton Wanderers might be back in the Premier League now, but the club had seen some of its worst days in the 2011-12 season, when they underwent a regime change in February, appointing an inexperienced Terry Connor as the head coach.
Connor was the assistant manager of the club for four years, before Mick McCarthy was sacked and he was promoted to his spot. Well, if someone is assistant manager for four years, it is expected of him to learn a thing or two about managing in that period, but that wasn't the case here.
He failed to win any of his thirteen games in charge, the club ended the season with just 25 points, lowest in their history and got relegated. Thus bringing an end to his spell in just 91 days.