The other poster is correct, but less exaggerated is

"when you bring in a new change to a technical system, you need to allocate time and resources to cleaning up after yourself, cause shit is gonna be broken. Could be big obvious things (should be planned for, but shit happens), could be that you patched over something with a temporary fix and it needs something more robust, also could be fringe cases that you aren't gonna know about for a couple months/years. The point is that every change you make incurs some debt to pay back, and you need to account for it if you want your system to keep running smoothly/relatively smoothly ".

SV techbros sometimes come in with the "move fast and break things" mentality, which is ok-ish (don't be afraid to mess up if you're genuinely trying to make things better), but you need to keep your house in order. Otherwise you're just building a tower of cards that's gonna collapse all at once beyond repair cause you're just moving fast and breaking thinga without allocating the time to stabilize them.