"The toughest thing to walk away from was this team," he said. "There are some things I'd love to see through but, when we balanced it up, it was a no-brainer.
"I'm doing the best job in the world but the toughest thing is being away from the kids. They just get to an age when they need their dad, and wives can have enough of it. I think a challenge for coaches can be uprooting their family to live somewhere else. Then your wife's forced to make new friends and find new schools while you're doing the same thing.
"That was a big part of taking the [Mumbai] offer. It allows us to live in Christchurch. My family don't have to uproot from where they're really happy and I still get to do something I love and spend more time at home. It was the best of all worlds."
Sources estimate an IPL assistant coach job would secure a salary of up to $150,000, meaning Bond would earn roughly as much as he does in two months as he does in a year as the national bowling coach. He can then supplement his IPL income with commentary or coaching consultancy work.
As one of New Zealand's most successful test cricketers, with 10 wins in 18 tests, Bond's impact on the current environment has been compelling, developing a bowling group of arguably unprecedented depth.
"I've decided what I've done has been positive but whoever comes in will enjoy working with that group [of bowlers]. Hopefully the job will attract someone who thinks, 'Gee, these guys can do some great stuff over the next five years'. I'm confident they'll get someone good to look after them. The attitude and talent is there. Whoever it is, I just hope I get the chance to share some of the IP [intellectual property] I've gained."
Bond's tenure started controversially when he wrote a letter to New Zealand Cricket backing former captain Ross Taylor's version of events over coach Mike Hesson in the 2012 captaincy saga.
He and Hesson have since mended their relationship. Bond was effusive in his praise for what the coach has achieved since.
"Hess was brilliant. He understood why I'm doing it and was completely supportive, which I really appreciated.
"I chatted to him about it [again yesterday] and we were saying all the coaching staff and management have kids of various ages.
"I always saw the job as a two-to-four year project. I'll have done almost two-and-a-half years by the end of the World Cup."
Mumbai will be coached by former Australian captain Ricky Ponting this season, which is set to start in April. Bond is the bowling coach and former South African player Jonty Rhodes is the fielding coach.
NZC's head of cricket Lindsay Crocker said they had been anxious to retain Bond's services.
"Make no bones about this - we're very disappointed to be losing Shane."
Bond's decision highlights a major concern for NZC as the national side's successes mount. Retaining quality coaches will be difficult, given the team can often be playing 10 months of the year.
"It's a challenge on the homefront because you're away so much," said Bond. "The thing is, if New Zealand Cricket has got someone like Mike doing a great job and continually improving things, how do you retain them for a long period?
"The answer at the moment is that it's probably unsustainable. You're away too much. If you stick at it, it's going to take its toll. Every time you go away it's bloody tough because it's for such long periods."
One possible solution to Bond's departure would be for NZC to appoint someone on an interim basis like they did with Craig McMillan as batting coach, rather than making a permanent selection. Either way, Bond believes the issue requires some serious thought.
"It's about trying to find a way of managing staff so they're not on the road as much, while still giving others opportunities and creating succession plans so when someone walks away you're not left in the lurch," he said.
