"... There was always going to be a period to see how things went from both sides.
"When you do something for 10 years you have a system and a way of doing things.
"I think the game's achievements have been there for everyone to see. We've come a long way in 10 years and I'm really proud of that."
Gallop acknowledged the move to unify rugby league's administration under the ARLC was the right one and predicted a bright future for "the greatest game of all".
"It's time for a fresh approach, I get that," said Gallop, who predicted a positive outcome for the game's crucial new broadcast deal expected to be worth more than $1 billion.
"I love the game and I wish it well, the job has been a great privilege and I've loved watching the game's resurgence."
"Ten years is a long time. If the next person does it for 10 years I'll be the first person to ring them up and take them to lunch."
Grant also insisted the move was mutually agreed and praised Gallop's contribution.
But he also described rugby league and the NRL as a "reactive" business over the past 10 years and said that needed to change in a new business climate with the new TV deal imminent.
"That context has changed totally, now there's an opportunity to think about it differently," Grant said.
"I think business today and the business that has been in the last 10 years is very different to the business that is going to be going forward."
Grant said the ARLC would immediately begin its search for a Gallop's replacement and while keeping his options open, hinted it could be someone with rugby league experience.
"A knowledge of this game and the passion behind it, I think you need to have that sort of experience, but I won't rule anything out," Grant said.
NRL general manager of strategy Shane Mattiske will take over the leadership in the interim.
Gallop enjoyed strong support of the clubs throughout his 10-year reign and the news he was stepping down from his high-profile role blindsided many of his fellow administrators.
Sydney Roosters chief executive Steve Noyce was taken aback at the news.
"I was shocked to be honest," Noyce told AAP.
"I was genuinely shocked and I think most people in the game are."
Sharks chairman Damian Irvine said Gallop had left rugby league better than when he began in 2002.
"When David took over we had a great game that was under duress, now we have a great game that is no longer under that duress," Irvine said.
Current NRL players and administrators of other major sports also paid tribute to Gallop, with AFL chief executive Andrew Demetriou labelling him an "outstanding administrator".
Gallop acknowledged his tenure had its ups and downs but had no regrets over controversies including the Melbourne Storm salary cap scandal.
"There have been challenging decisions but I always saw them as opportunities to put a stake in the ground for the game and what the game stands for," Gallop said.
". ..I wish the game good luck and I say thank you, it is the greatest game of all."
- AAP
