Wilshere is out of contract at the end of the campaign, and while the club remain optimistic a deal can be reached, they were content for him to leave last summer.
Preparing for England's international friendlies against Netherlands and Italy, Wilshere said he was granted the opportunity to leave boyhood club Arsenal following his season-long loan spell at Bournemouth in 2016-17.
"It was an honest conversation," Wilshere said. "It had been boiling up for a while.
"Everybody knew I had a year left on my deal and had been out on loan, got injured and wasn't really in his plans. He just said: 'At the moment we are not going to be offering you a contract so, if you can get one somewhere else, you can go.'"
Wilshere, though, has forced his way into Wenger's first-team plans this term, making 31 appearances across all competitions.
The 26-year-old continued: "Obviously I wasn't happy with what the manager had said but, at the same time, part of me knew all this already.
"All I needed was some clarity on where I stood at the football club. How did I feel after? It did make me think. He'd said I could fight for my position and, if I performed well in the Carabao Cup and Europa League, I'd have a chance.
"I had three or four weeks left in the transfer window but I didn't find anything I wanted and at the same time I wasn't really fit. So I decided to build up my fitness. I always had confidence I could get back into the midfield, and keep my place, if I was fit.
"I'd been in a similar situation the previous year. I'd come back from the Euros and picked up an injury in pre-season and, for the first few games, I was not in the team. I knew I had to play at that stage of my career because, the year before, I had missed a lot of football [an ankle injury had restricted him to three appearances for Arsenal]. I couldn't just be coming on from the bench, so I went to Bournemouth. A lot of people disagreed with that decision but I played a lot of games and proved to myself I still could.
"So when the boss said I could leave, I wasn't still thinking: 'I need to get out and play games.' It was more of a case of getting fully fit and showing what I could do. When I was at Bournemouth, getting back here was always the aim. This is where I wanted to be."