Thompson was unveiled on Thursday afternoon as the Bombers' interim senior coach during Hird's 12-month suspension, with Neil Craig appointed - on a two-year deal - to the new position of head of coaching, development and strategy.
While two-time Geelong premiership coach Thompson had been adamant initially that he had no interest in filling in for Hird, he said on AFL 360 on September 24 that his love for the game had returned and on Thursday he said he had experienced a dramatic shift in sentiment.
''Freshening up is a natural part of the process. You go through it every year,'' he said. ''A couple of weeks' later, I thought about the football club and how I was looking - I'm [now] happy to be part of it.''
He said on Thursday he had spoken with a few of the club's players to convince them he was ''very, very committed and excited'' about leading the Bombers.
''Clearly, they didn't want a coach that was just going to sit idle, that wasn't going to do a great job and give them the best opportunity to be the best that they can be. They did want to know whether I was committed,'' he said.
''I've openly stated in the past that I didn't want to coach. Well, I think I really wanted to do it for nine months [of 2014], and that's what I'm going to do.''
Thompson rejected the suggestion that a sense of obligation to the club, as it searched for a replacement for Hird, triggered his acceptance of the position. He said he was driven by a belief he had underachieved as Hird's senior assistant.
''I think I've been a little disappointing in my role over the past three years. I haven't achieved what I wanted to achieve. If I walked away now I haven't set out what I wanted to achieve, and that was to make Essendon a better football club,'' he said.
''I'm a pretty proud man and I think the way people are looking at Essendon is not what I'm wanting them to see.
''We just want to build again. We want to build respect, we want our fans to love us, we want supporters from other clubs to know, 'Yeah, they're a pretty professional club and they play a fair game and they're pretty decent people'. I don't think they're looking at it that way at the moment.''
While Hird will be eligible to reclaim the senior mantle from Thompson in time for next year's finals series, chairman Paul Little revealed that Hird had lobbied the board against that option.
''James' view was that it would be unwise to come back and take up the coaching again right at the end of the year, so the decision was taken very early in the piece that that wouldn't happen,'' the chairman said.
Thompson said Hird ''won't have any active involvement in how the team's going'' until at least late in August, but stressed he would not be changing tack in the club's playing and coaching strategy.
''We're in great shape as far as a lot of things we've done over a three-year period. We're not going to redo it ... it's just going to be added to,'' Thompson said.
Little said once the club settled on the appointments of Thompson and Craig - in which Hird, he stressed, had had no involvement - it organised a half-day meeting between the two to gauge their suitability to work together.
''You may think they come from opposite ends of the spectrum when it comes to personality types and approach to the game [but] I'd have to say we're terribly excited about the chemistry that has become very apparent between the two of them,'' he said.
Little praised unsuccessful applicant Simon Goodwin as having been ''a very strong candidate for the job''.
As a result of the changes he has been promoted to Thompson's old position of senior assistant.
Thompson admitted his role after next season was uncertain but insisted he had no qualms about that because of the opportunity presented to him as interim senior coach for 2014.
He said he was hopeful, but not optimistic, of persuading forward Stewart Crameri to remain at the club. He also did not rule out the possibility of drafting veteran forward Paul Chapman, whom he coached while at the helm of the Cats.