Speaking at his end-of-window press conference, Fabiani explained the thinking behind Lazio's decision not to fill every available registration spot before the deadline.
"There's still the free-agent market open, I preferred to leave some slots free to monitor it too," he said. "The rules allow us to add players back to the list at any point, even those who haven't been included so far, but I also have to say with complete honesty that there are some excellent players, some extraordinary lads, who simply don't fit into the club's future project.
"I say that to avoid any misunderstanding and to be straightforward — the agents knew well in advance what the club's thinking was."
Fabiani also addressed his working relationship with head coach Gennaro Gattuso amid a difficult summer that saw Alessio Romagnoli depart.
"With Gattuso there's a straightforward relationship built on real correctness and mutual respect," he said. "On Romagnoli, we're talking about something impossible to pin down — for two months, it wasn't me, it wasn't Lazio, who put out a storyline with an ending that simply didn't exist.
"Did some clubs want to get him for free? That was never going to happen. In the end, the deal that went through yesterday was the one originally agreed with the club. Gattuso knew perfectly well that Romagnoli wanted to leave, and he's been clear he wants players who want to be at Lazio."
The sporting director confirmed Gattuso had personally blocked a move for winger Matteo Cancellieri, turning down interest from Genoa, Parma and Fiorentina, a decision that in turn delayed the club's pursuit of Albert Gudmundsson.
"Gattuso called for these players, and for me that's a source of real pride, because it's Gattuso this club has backed," Fabiani said. "We've had conversations with him, we've handed him the keys, and he's our leader."
Asked whether he had considered resigning given the pressure around the club, Fabiani was candid about the personal cost of the summer.
"I understand the question about resignation, but you have to be intellectually honest," he said. "Everything passes in life — presidents pass, directors pass, coaches and players pass. I've had to manage a difficult situation with passion, dedication and a sense of belonging.
"Results don't concern me as much as the fact that I haven't had a single day off with my children — I've been shut in here working for Lazio. To get results you need conviction, and Gudmundsson is proof of that: a month earlier they wanted five million for him, a month later I got him for what I believed he was worth.
"I could offer my resignation, or people can talk about a contract renewal — I'm not here for money, I'm here out of passion. My commitment runs until the end of the season, and then the club will judge the work. I turned down 25 million from Milan once, I gambled on five million instead and we ended up making 30."