Because the window that is quiet for them is the middle of your working day. A schedule built around headquarters hours lands planned work, patching and reboots squarely on local trading time, and the further you are from the decision the more likely that goes unnoticed for years.

It tends not to be raised because each individual instance is small — an hour here, a restart there — and the local team absorbs it. What accumulates is that the site never gets a genuine maintenance window of its own, so deferred work stays deferred and hardware that should have been swapped during a quiet period never is.

Components that ought to be replaced on a schedule get replaced on failure instead, because there was never a convenient moment. Controller batteries and power supplies are the usual casualties, and they fail during business hours since that is the only time the system is under load.

Hold the parts. A repair that can be completed in minutes by someone on site needs a much smaller window than one that waits for a shipment, which makes it fit inside whatever gap is actually available.