"""Three major themes that cause “bad days” for developers: tooling and infrastructure issues, process inefficiencies, and issues around team dynamics. Within those issues, deeper concerns were identified and are shared in the following sections."""

The causes will sound familiar to most developers here. The most significant causes are usually outside the person's control, as expected. Interestingly, "interruptions / randomness" was only the sixth most significant, while the most significant cause was "engineering system friction."

The average number of "bad days" per month is 3-5. Accounting for weekends and vacation days, that's nearly 20% of the time! And some report 9+ bad days per month.

So, if you happen to work on corp-infra or other tooling/support role, and you occasionally lament that your work is not in the critical path, you actually have a rather large impact if you think of it in terms of helping reduce the number of bad developer days.