Gary Neville accused the Manchester United hierarchy of lacking any clear strategy following the sacking of Ole Gunnar Solskjaer.
Former United skipper Neville said the United board had been "caught out" by the team's collapse under Solskjaer and had failed to put a contingency plan in place.
"They haven't planned for this, they haven't prepared for it," said Neville. "It's deteriorated so badly and so quickly.
"If there was a world-class manager sat on the shelf ready to go, I think Ole would have gone two or three weeks ago.
HAVE YOUR SAY! Who should Man Utd appoint to replace Solskjaer? Let us know in the comments
"Manchester United's board were never going to appoint Antonio Conte. He wasn't a fit.
"This is the third time in the last eight years that a manager has been given a long contract or an extension and been sacked. I've had enough, to be honest.
"The club is run on a business side okay, but on the football side it leaves a lot to be desired. They've been caught out over the last few weeks. They've been indecisive.
"I think getting to the end of the season was the right plan but yesterday it was quite clear those players weren't responding to the manager."
Neville had steadfastly refused to call for former team-mate Solskajer to be replaced, but accepted the United hierarchy had little alternative after such a poor run of results.
"In the past he's always had that result to pull him out of the mire," said Neville. "This time the results have got worse and worse and worse.
"The team have been all over the place. The first thing is the performances. The team have looked all over the place.
LIVE: Follow all the latest from Old Trafford after Solskjaer's sacking right here
"The defending is absolutely woeful. The goalkeeper, the defenders, and that's a back four, a back-five, who have played with each other a number of times.
" Watford aren't the best team in the league by a long stretch but Manchester United got mauled. Ole couldn't get a performance out of them in the end.
"The players look drained of confidence and I'm not surprised that it has ended.
"I said a few weeks ago, the worst that could've happened for Ole is that he became a bridge from what would be quite a dark period to the club to what I think maybe, hopefully, a positive future for the club.
"They need to get the next appointment right and that'll probably be at the end of the season.
"Seven or eight weeks ago there was euphoria at Old Trafford and it's just deteriorated.
"I've never been there in a dressing room where the players have felt so drained in confidence.
"I don't think they are players who don't care. I don't buy that. I think they're a good group of lads. They've looked rudderless on the pitch, rudderless off the pitch."