Slack
Very nearly every company I've worked for seems to have a constitutional aversion to "slack" in the work pipeline for development. Sometimes this manifests as a pile of inward-facing operational development that passes hands every few weeks and never really gets done because as the current developer is urgently re-allocated to a paying client. In consulting, sometimes it just means a stretch without pay when there's nothing to bill on. Sometimes it results in developers being assigned increasingly low-value, low-clarity, or low-interest busywork.
All these things are an extremely poor usage of available developer resources.
These situations seem to originate in a view of engineering manpower as either a cost center (e.g. in an IT department) or a kind of inventory (e.g. in a contracting/consulting firm). For accounting purposes, fine. But that doesn't mean you have to actually treat them that way. I'm not sure if my view is any more valid, but I tend to think of engineering slack as a surplus. We have the developers' time. It's probably paid for. And even if it's not, it's probably bad for morale not to pay for it. Sure you can burn off the excess and get not much more than waste heat out of it. Or, you can invest it, and make back the cost in dividends.
Nearly any company has systems that can benefit from a little more automation, a little more customization, a little more integration. This is what the vast majority of developers in business are doing. Most of them are just doing it because the work is going to actively mitigate an operational cost or support a revenue stream. Sometimes the direct value added isn't worth the cost of the developer's time. But good engineering often pays dividends in indirect value, via force multipliers or ongoing and compounding efficiency.
Not all work is created equal, but if you look carefully, there's probably some benefit to be had from a little extra development time. And the next bit can compound on that. And the next. And the next. Before you know it, your operations could be humming like finely tuned machinery. Or you have an experimental beta feature that could be your next surprise hit. But you'll never know if you keep burning off your excess instead of investing your surplus.