Szafnauer departed the team after last month's Belgian Grand Prix as part of wholesale changes at the Enstone outfit, with long-time sporting director Alan Permane also leaving.
The news followed the departure of Alpine CEO Laurent Rossi, who was moved aside by Renault CEO Luca de Meo to a position away from the F1 programme.
At Spa, interim team principal Bruno Famin said Szafnauer and Renault were on "different timelines" in terms of cutting short Alpine's five-year plan to fight for wins and championships.
Talking to SiriusXM, Szafnauer says he "couldn't agree to an unrealistic timeline" with de Meo, saying the Renault management had a lack of understanding of what it takes to be successful in F1.
"I think the senior management at Renault, CEO Luca de Meo, as everyone does in F1, wants success instantly and unfortunately, that's not how it works in F1," Szafnauer said.
"They wanted to do it faster than is possible and I couldn't agree to an unrealistic timeline because if you do that, it's only a matter of time and everyone gets frustrated, so I laid out a very realistic and possible plan and I think they wanted to shortcut that plan with somebody else."
Szafnauer pointed to Renault's lack of patience over his recruitment plans as a symptom of the underlying issues.
He revealed that when he started at Alpine 18 months ago, he found several gaps in the Enstone team's know-how. Plugging those holes by attracting staff from rival teams, who are generally on long-term contracts and subject to gardening leave, involves long lead times.
According to Szafnauer, Renault's lack of understanding of that process meant he couldn't get that message across to his bosses.
"There are pockets of the organisation that the skill level is at a very elementary level and that's because the people they have there were college graduates, for example, as opposed to somebody with 25 years of knowledge.
Source: Autosport