It's super common, generally, that when your work environment is super shit, or you're overloaded with work, people get "sick" more. There's an actual metric for measuring the impact this has on businesses, it's called the Bradford Factor.
You start to see patterns in sickness, such as certain times of the year, certain days etc. I'm not saying Pogba is aware of this, but I promise you his 50% injury record he currently holds at United will massively recover at least 20% during his next contract.