A phrase like "predictable" can mean many different things to different people, but it can also be vague. It also refers to timelines and dates, which are affected by many variables outside of a developer's control, so no one should be held accountable for something they can't control.
As long as it's clear why things are happening, the team can still be healthy when expectations change, shift, or are entirely reset. Although teams can't always be predictable due to unpredictable industries or organizations, they can still set clear and realistic expectations.
For example, one of our clients was obsessed with predicting team performance as a measure of success. If the team failed to deliver work on time consistently, they would make estimates for the work that would come their way. Since we were reinforcing "on time" instead of quality, agility, or anything else that would create additional value, the teams naturally added more buffer.
But then, the teams were criticized for taking too long on projects when the needle swung the other way; however, they were expected to make an estimate and honor it. As a result, morale plummeted, defensiveness increased, and it became essential to find someone else's fault for everything that went wrong. [Not a good long-term talent retention strategy]
At Framework Science, we manage nearshore software engineering teams in Mexico and Colombia around realistic expectations. When doing work research, we do not know everything, so our stakeholders are not surprised when things are unclear or fuzzy. Reprioritization is also a good thing. When working with realistic expectations, something else may arise.
It is okay to work on two things at once or to put one thing on the back burner while you focus on another. Ultimately, we want our stakeholders to make the best decision for themselves by identifying the impact, sharing pros and cons, and sharing opinions with the team. There will be changes to deadlines, but the team is still delivering what they promised, even though some would consider that "unpredictable."