Ulster's scrum cornerstone will quit Ravenhill at the end of the season to switch to the Aviva Premiership and the Cherry and Whites.
Gloucester have secured the 30-year-old tighthead's services on a long-term contract, fighting off a host of English and French suitors, as well as the New Zealand Rugby Union.
Afoa's family were unable to settle in Northern Ireland, returning to New Zealand last year, and t he 36-cap front-rower had been expected to return to his native Auckland next summer to fight for a place in Steven Hansen's All Blacks squad.
But Gloucester's rugby director Davies revealed Afoa will aim to reunite with his wife and two children at Kingsholm next season instead.
Davies said: "His family played a big part in it all.
"One of the problems he's had at Ulster is that his family didn't really settle there and have gone home, so that's put a bit of pressure on him, understandably.
"So that was fundamental in the decision-making process and, if we're being frank, he could have gone to France for more money.
"It had to be right for him and his family.
"He feels his family can settle here.
"John sees Gloucester in a similar position to where Ulster were a few years ago.
"Ulster have had a big investment programme over the last three to four years, recruiting real quality players, and that's impacted on their performances.
"He can see parallels with the potential there was at Ulster as there is now at Gloucester.
"He wants to bring his family across from New Zealand and he can see them settling for the next few years in Gloucestershire.
"Jimmy Cowan met with him and spoke candidly about life at Gloucester, (co-owner) Ryan Walkinshaw and other board members were involved in selling the club to him too."
The IRFU's whopping 26million Euro deficit from their well below-projected five and ten-year debenture seat sales in July will impact most heavily on the Irish provinces.
Ireland's RaboDirect Pro12 clubs will be asked to pick up more squad budget costs than ever before for next term.
The squeeze will only inhibit their bargaining and buying power where high-profile imports like Afoa are concerned.
Ulster have been able to retain Ruan Pienaar on a new deal but across the board the Irish provinces have to tighten belts.
Gloucester boss Davies said Afoa's capture signals a return to heftier squad investment from the Cherry and Whites, especially in their tight-five.
Further front-five recruits are in the offing at Kingsholm, though the club are yet to confirm a deal for Ospreys hooker Richard Hibbard despite widespread speculation he will follow Afoa to England's south west.
Davies said: "It is absolutely a statement of intent.
"It signifies a clear change in direction in terms of strategy for the team.
"The side has gone a particular way for the last four or five years in terms of recruitment and the rugby it wants to play.
"And I think what's been evident is that particularly in the Aviva Premiership, your ability to compete up front is your most important facet really.
"We just need to bring that steely forward pack edge back to Kingsholm, which is what we've traditionally been known for.
"I think Kingsholm lends itself particularly well to a forward pack dominant on the front foot, and that's what we need to get back to.
"This is part of that process.
"We've got a reasonably young pack of forwards, so to bring some front-five players in of this experience and quality will add to what they currently are as well as what they do as individuals too."
- Sports & Recreation
- Aviva Premiership