Adopting change management best practices reduces the risks in any business transition. The first time, the second time, the last time, and the next time. The risks may be technical or reputational, but always financial.
This applies not just in the IT area, but also elsewhere in the enterprise.
The main resistance to implementing change management are claims that it is bureaucratic: a needless overhead.
Perhaps the team's guru for a particular task is on holiday. The guru knows exactly what to do, and everybody in your team more than half feels they should too. The team knows about second order ignorance however, and none of them want to be the one's putting their head in a noose.
Your team have done something dozens of times, but the person doing the work got distracted and they've missed a step that in their own mind they're sure they've done.
Your nature is trust but verify. What if you're not sure how your team should verify? In a cricket analogy, are the wicket keeper and long-stop doing the verify okay? [Translation for Americans: in baseball, the catcher and the fence behind the catcher.] As far as your processes are concerned, you want to make sure the long-stop / fence is not your customer.
In change management there's a concept of "Maturity Index": the five levels are shown in the diagram below. The journey you want your team to take, from where they are to (perhaps level 1 or 2), to where you want them to be (presumably level 5) is not going to be attained overnight.
With assistance from somebody who's travelled that road before themselves, and helped others to do so too, it should be quicker.
For more information on how we can help you with improving change processes, and reducing transition risks, please write to firstname.lastname@example.org.