The British billionaire assumed control over the Red Devils' football operations last year after investing £1.3billion for a 28.94 per cent stake.
In the last 12 months, INEOS chief Ratcliffe has seen United lift the FA Cup, while also being witness to them recording their worst Premier League finish last season.
United ended up in eighth place, but they look set to come even lower than that this term; the club is languishing in 14th spot with ten games to go.
Still, Ratcliffe saw it fit to hand Ten Hag a new one-year contract extension until 2026 last summer after he secured silverware for a second season running.
But it proved to be an unwise decision, as United sacked the Dutchman in October, with it costing them £10.4million in paying Ten Hag and his staff off.
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Meanwhile, Ashworth lasted just five months having been appointed as United's sporting director after making the move from Newcastle., setting the club back a further £4.1m.
He oversaw a £200m summer spending spree on Leny Yoro, Matthijs de Ligt, Joshua Zirkzee, Noussair Mazraoui and Manuel Ugarte.
But ex-FA chief Ashworth was moved on after 159 days with Ratcliffe becoming frustrated by his decision-making - a costly decision worth £4.1m.
And speaking to The Telegraph, Ratcliffe has opened up on the dismissals of Ten Hag and Ashworth where he accepted responsibility over the mistakes.
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He said: "They were just mistakes. The Erik thing is slightly mitigating. There was quite a lot of debate about that time.
"He had just won a cup final. The fans were clearly of the view that we'd like to stick with him and all that sort of stuff.
"They were both mistakes. I don't think we can say much more than that.
"It's a journey and there's a lot of decisions that we have to make over the course of the journey and we're not going to get them all right.
"I don't think in the future we'll get them all right either because we're not perfect."
Pressed on why him and Ashworth couldn't work together, he stated: "We're talking about our old industry [with INEOS].
"I think we just have to say, 'Chemistry'. Really, I don't want to go down that [road]. It is what it is, and it was our fault."
As for Ten Hag, he then remarked: "There was an emotional response [after the FA Cup].
"We get criticised for being unemotional and there was a bit of emotion in that decision.
"I think [new chief executive Omar Berrada] had only been there about a morning.
"Jason [Wilcox, technical director] hadn't been there very long. We didn't have many experts in play.
"Really, I'm not an expert. And it was hard to extract him [Ten Hag] from the former management set-up."
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Following Ten Hag's sacking, Ruben Amorim was brought in, but the club have not experienced a 'new manager bounce' under his tutelage.
The 40-year-old has lost nine out of his 26 matches in charge in all competitions, and has overseen United crashing out of both domestic cups.
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