The one I've seen missed most often in startups is directly implied by a lot of the other points and obvious to anyone with long experience: Take the time and put a lot of thought into how to break up your big transitions into smaller stages, each of which are functional. It's usually possible to at least narrow down the risky parts to a few finer grained steps and when something fails only rolling back one part to get to a good state is almost always faster and safer.
It's very easy to get absorbed into the awareness of the high level change you're making and miss the details of the process. Even just sitting down together and outlining what you think is actually going to go on (and then breaking those down into what they each are comprised of) can make it really clear that you don't have to run as many giant risks. I'm occasionally amazed how brilliant people (including some with big names in devops) can forget it's an option.
It's like taking small steps from stable to stable when you're going across a steep scree slope and only jumping when you have to - sometimes it feels riskier to take lots of small steps, but if you start to slide it can be a lot easier to recover from. Your chance of dying taking a big leap isn't the sum of the equivalent small steps. Perhaps complex computer systems have the equivalent of an Angle of Repose?
It's very easy to get absorbed into the awareness of the high level change you're making and miss the details of the process. Even just sitting down together and outlining what you think is actually going to go on (and then breaking those down into what they each are comprised of) can make it really clear that you don't have to run as many giant risks. I'm occasionally amazed how brilliant people (including some with big names in devops) can forget it's an option.
It's like taking small steps from stable to stable when you're going across a steep scree slope and only jumping when you have to - sometimes it feels riskier to take lots of small steps, but if you start to slide it can be a lot easier to recover from. Your chance of dying taking a big leap isn't the sum of the equivalent small steps. Perhaps complex computer systems have the equivalent of an Angle of Repose?