Dyche was removed in February just days after he had been nominated for Manager of the Month.
Asked if it's hard to understand why he lost his job, Dyche told The Football Boardroom podcast: "Well, I don't. Statistically and factually, no emotion to it, if you look at the stats and facts, even after the last game against Wolves.
"Our current form at that time was ninth in the Premier League. The stats and facts were there, clear as day.
"From my record, from when we got there to when we ended, we'd have been 12th in the Premier League. So on factual data and analysis, I can't understand any of the decisions that were made. But football is changing, and we witnessed it."
On the rumours of him falling out with the Forest dressing room, Dyche is again baffled.
"There is a lot that was coming out - that the players are tired because they (Dyche and his staff) are working them too hard," he said. "Since when has that become a currency that is almost like, oh, what are they doing working footballers too hard?
"If you'd have written that 10 years ago, people would have asked what they were talking about and thought they (the players) should be in there every minute of every day. I mean, I couldn't believe it, honestly. He's working the players too hard?
"I'm like, when did that become a bad thing? I'm scratching my head. Me and my staff were going: 'Well, we've got all the data, the stats and facts.' Lowest physical performing team in the Premier League when we took over, so what do you want me to do then? Not get them fitter? I mean, it's just madness, right?
Keyboard warriors
He went on: "This is where I was saying about the 10 per cent of football life now - keyboard warriors, media, whatever you want to call it - that for me is a coupon buster. The players were working too hard? I have never heard that as being a negative in my life.
"I cannot fathom that out where we're asking the players to work hard for a football team and wear the badge with a bit of pride. We all know, as managers, the walls talk. I know the runners and riders in all of my career. I certainly know the ones at Forest. But they'll get weedled out, because life is like that, they will get found out."
Dyche insists there's no grudge against Forest owner Evangelos Marinakis: "I need to make this clear - this is really important to me as a football person and as a person - Mr Marinakis was nothing but good to me and straight.
"His final decision is a strange one, but as a bloke, with me personally, I've got no gripes at all. Nor over his son, Miltos, or the powers that be, no gripes at all."