I always make sure HR does not include “multitasking” in the job description.

That is bad. All-around. Bad management, bad budgeting, bad strategy.

Multitasking is wasted motion.

Harold Pashler has shown that people can only think about one thing at a time, and switching between tasks creates delay and interference. Gerald Weinberg  postulates that Adding a single project to your workload will drop productivity by 20%

Why do we do it? The human brain seems to enjoy it. After all, it did not evolve for project management, but rather hunter-gathering. Interest in new stimuli insures You don’t miss that delicious snack or deadly predator.

Don’t multitask. Even if it feels good.

Further reading:

https://www.solutionsiq.com/learning/blog-post/agile-resolution-1-destroy-multi-tasking-the-productivity-killer/

https://turboscrum.com/context-switching/