It can be deadly on a hike. It’s costly for a basketball team.

Chemistry must be rebuilt. No steps can be skipped, regardless of how long a team has played together.

“You’re starting all over,” Knicks coach Mike Brown said after practice Sunday. “It’s like climbing a mountain. We’re climbing a mountain as a team and we conquer the mountain, then you gotta come back down, take some time off, then you gotta climb another mountain. It’s the same thing. And when you climb that mountain the second time, you’re starting from base camp again. And if you skip steps doing that, you’re going to die. It’s not that tragic for us. When you’re sitting at 2-4, people equate it to that sometimes, but it’s the same thing, taking each step the right way and embracing it and trying to get a little better.”

The Knicks’ continuity from their championship team was supposed to be a major strength for their chances of repeating. This group clicked about as well as any group has ever clicked during the playoffs last year. Their togetherness and selflessness made them new fans across the country. An ability to elevate each other on the court made them an incredibly well-functioning machine.

But with a 2-4 record through the first six games of the year, the Knicks have resembled a group that, as Brown said, is starting all over again — not one that is picking up where they left off last year. It’s been most glaring on the offensive end, which has been disjointed. There have been too many turnovers, too much isolation and a lack of playing off one another.

It has looked like a group that is relearning each other despite the core knowing each other better than any in the league.

That’s the tricky part about chemistry — it needs to be reestablished and reinforced, like a campfire that constantly needs to be tended to.

“Yeah, that’s why I think for us, we just gotta continue to grow,” Mikal Bridges said on Sunday. “Last time we played was in June. I think [we were] probably the most polished as a team we were at the end of the year, as we should be. So, I know it’s tough to see last time we played to the beginning of the year, and obviously we should be better than we are, me personally. But it takes time and just not skipping steps and just kinda going through the process and keep learning, get back in that rhythm.”

It was similar last year, when the Knicks started 2-3. The offense was a constant — and frustrating — work in progress all regular season. It’s hard to remember with how the season ended, but Karl-Anthony Towns’ involvement in the system — or lack thereof — was a recurring storyline.

There was ample criticism that he and Jalen Brunson were basically taking turns looking for their own shots rather than utilizing a two-man game and playing off each other. Until, all of a sudden, it all clicked and the Knicks played their best basketball when it mattered most.

Brown likes to experiment in the regular season. As they try new things this year, it means a return to that work-in-progress version of the Knicks.

With the belief that as that chemistry re-forms, those championship results will return, too.

“If we don’t go through our growing pains and we can’t get through our growing pains, for whatever reason — because we don’t want to go through it being that hard again or we think we know or whatever it may be — if we can’t get through our growing pains, we have no chance,” Brown said. “It’s like anything you do in life. When you complete something and you have to do it again, you’re not just starting right here [at the top] when you do it again. You’re starting here [at the bottom] and you’re building up. And sometimes, your second or your third year doing it, you’re getting here [at the top] a little quicker. But you still gotta go through all the necessary steps to get there.”

This is one of those necessary steps.