Last week, Fry was announced as Williams' new CTO, having departed an Alpine team in turmoil after its upper management sacked team boss Otmar Szafnauer and long-time sporting director Alan Permane.
The deal to sign Fry, who is set to take up his position before the end of the year, predates Alpine's flurry of management changes by several months.
According to Vowles, the coup to convince the experienced engineer to join Williams shows that his squad is serious about wanting to implement significant changes at Grove on its long journey back to the front.
When asked by Motorsport.com if Fry's marquee signing can be the catalyst to more high-profile personnel making the jump, Vowles replied: "In part. But I hope that for a start, when people saw that I left the comfort of Mercedes to go to Williams and now people have seen Pat, at a time where Alpine was in a strong place, people will now understand that Williams wants a culture of change.
"So, it's not specifically that. It's more that once you see two very senior people that have been in the sport for 20 plus years and winning races and we want to come here, others will now see why it's worth that journey."
He added: "That's why I wanted it to be clear this wasn't in the last few weeks. This was a long time ago wanting to join Williams."
Vowles revealed his first talks with Fry date back to January, as he had quickly identified the former Benetton, McLaren and Ferrari stalwart as a key figure in implementing a new technical structure at the team, while freeing up Vowles' time for more strategical thinking.
"The first times I spoke to Pat was actually back in January before I'd officially started with Williams," he explained. "Just to make it clear, he was the one I'd highlighted that I really wanted to be within Williams.
"He's exceptional at coming into organisations when you need someone to pull their sleeves up and properly get stuck into structure and systems.
"There's different types of CTOs available to you. There are ones that are very good at finding your last 10 milliseconds. There are ones that are very good at putting structures and systems in place, and he's more the latter.
"He understandably had a journey with Alpine that he wanted to continue. But actually, by April he could see the vision as to why I had joined Williams and was very much in line and on board with that."
Williams's next major hurdle is to appoint a new technical director reporting to Fry, but while Vowles has identified "several" potential candidates for the vacancy, he said "there's nothing to talk about at the moment".
Additional reporting by Adam Cooper
