"You get to a point in politics where you've got to rejuvenate something, and that always seems to happen after a long spell in government.
It happened to the Labour Party as well, McKelvie said, and it was happening to his party in the exact same way.
McKelvie said he thought the withdrawal of Simon Bridges from the leadership race was "probably always going to happen".
"I guess with these things sometimes you've got to push it as hard as you can, and then see where it ends up."
McKelvie said Collins had entered the leadership role in extraordinarily difficult times.
"The election definitely gave us a bit of a hammering and dented our confidence, and hers too I think.
"Given the time she came in here and the things she had to put up with, I think she did very well."
His party now needed to give people a credible opposition they can vote for if they weren't happy with the Government, he said.
Former National MP for Whanganui, Chester Borrows, said he hoped Luxton could hold National's MPs together and they could "get the bit between their teeth".
"Obviously the change in leadership is one that needs to be enduring," Borrows said.
Borrows said the regular change of National Party leadership mirrored that of Labour before Jacinda Ardern.
"It's like any other relationship, whether it be personal or business, the honeymoon only lasts so long and then it's down to hard graft."
Collins hadn't left a positive legacy, he added.
"Given the proximity to the election when Todd Muller stood down, Judith was probably the best call they could make at the time.
"In the end it was a horrible result, and it was probably always going to be.
"I think it was timely that she left. She brought it on herself and karma exists, karma is a real thing."
Whanganui-based National list MP, Harete Hipango, was contacted by the Chronicle for comment.