The Cherries were 2-0 down with 87 minutes gone at Goodison Park against the Toffees.
However, they emerged with three Premier League points, winning 3-2 thanks to a late Luis Sinisterra winner.
Speaking to the media after the game, Iraola stated: “I think we needed something to happen because it's true that I was feeling that physically we were finishing strong with the subs, with Antoine, Tav.
“I think they were starting to make the difference, one versus one.
“But probably it was too late and we needed something to happen to really start to believe and also to make them fear a little bit because they were think they played very well and they had the situation under control most of the game.
“Once we scored the first one, probably this has changed.”
On what he told his side to change, he added: “We always ask them to change things, especially when you are losing.
“Sometimes (they) work, sometimes (they) don't work. But I don't feel like I've done amazing substitutions.
“I put Dango left back and then something has happened from that, no, no.
“I think it's 99 per cent merit of the players, of the change of attitude, the willingness to revel in front of a difficult situation and this spirit that they scored 2-2, and go quickly and they have another chance and then Pickford makes a save.
“They keep pushing and believing and making everyone feel like they are going to do it. And this is everything from the players for me.”