The 39-year-old has been discussing one of the low points of his season.
The Norwegian had come in for heavy criticism during the start of his Bhoys career and admits he became disillusioned with the emphasis constantly being on results at Parkhead.
Things have now improved, however, according to Deila, but the Celtic boss's comments may come as a shock to many fans - as he has always given the impression of rising above any criticism aimed at him. He is human, it turns out...
“There was a period when I doubted whether I wanted to do it (manage Celtic). I felt it was a bit unfair at times. I’ve always said I want to build things, create things," he told reporters.
“When you come in and everything is result, result, result, it’s tough to think how you are going to fix this. If it’s only about results it’s not fun. If I have to go in and think, ‘I can’t make mistakes today’, there’s no development there.
“But we’ve got past that stage and we are really getting better and the culture’s getting better."
Should Deila really be so anti-results, though?
Considering the flak the Norwegian received at the start of his Celtic reign, he wouldn't be human if he had his doubts. No one is blaming him for considering his future; no one would have questioned him if he lost it with his critics.
But, as much as he speaks of development and progression, football is a results business. The 39-year-old is going strong at Parkhead but his philosophy sounds idealistic. 'Fun' is one thing. Winning is reality.
After all, it is results themselves that are going well right now - and that's why Deila is getting all the praise. One must always keep an eye on the future but never forget to win in the here and now. Especially at a club like Celtic.