Bridges was asked by a reporter if Joyce knew he was not getting the finance portfolio before retiring. He said yes and that he did not think the decision caused Joyce to resign.
"Ultimately Steven has decided not because of that but for his own reasons in terms of his family and getting back out into the world of commerce and the opportunities that are there."
Bridges said Joyce was a loss for the party, both as a colleague and as a friend.
"I wish him all the really best for his future. I know that I'll be able to call on him for really good advice, given his experience both in the economy but also in relation to our campaigns, having done such a successful job for us as campaign manager over successive elections."
The appointment will pit Amy Adams against Finance Minister Grant Robertson.
Read more: Amy Adams appointed as National's new finance spokeswoman
Bridges said earlier today that National intended to fight the Labour-NZ First-Green Government's plans for the economy, including any tax changes it agreed to from the Government's Tax Working Group.
Adams was considered Bridges' nearest rival in the leadership contest.
At the press conference this afternoon, Bridges said he did not expect any more resignations over the next few days and in the lead up to more announcements.
But he said over time and over the course of this Parliament, "you will see other retirements from the National Party caucus".
"But I wouldn't expect a whole lot of them.
"I think it's about making sure we are blending that good experience – because we want to keep that – with new talent coming through. And you wouldn't want to see too much of either of those things. You've got to get that blend right."
He said the appointment of Adams did not signal a significant shift in the way National would handle its policy.
"We're not radical by any stretch and I think we know we don't mess with success. We've built up an incredibly strong legacy in the economy for this Government ..."
Bridges did not give much away about the upcoming reshuffle.
"You've got to get things in the right order and what we've done today is show you our top three ..."
He said in the next few days and certainly before the end of next week, he would announce his reshuffle in total.
"You'll get to see how we have blended that experience with fresh talent coming through."
Bridges said it was an exciting line-up that will capture New Zealand's interests.
He said there would be fresh faces coming through the ranks and also some experience remaining.