The price tag for Pogba that Man United is willing to pay is less than his potential value at United. It's not only that they need him for a successful campaign but it's also because of his potential value in shirt sales and ticket sales. Pogba may be overrated today, but wait until he reaches 28 - 30 years old. United might be back on the top by then and sales of Pogba (no.18 or 22?) shirts will be worth way more than the 100+M Euros they paid for him.
Of course in the end it doesnt matter how much they are going to waste on signing pogba because they will be able reach their ROI just by selling shirts however talents could be wasted, dimaria was a good example of that and his shirt was quite the trend back then and yet united sold him due to his bad performance
Thing is, not everyone belongs in united, not pogba obviously
I think manchester united want to buyback pogba because mourinho is need play who will play as box to box midfielder cause as a number 10 manchester have many option and for financial pogba not a famous player like zlatan so manchester united just spend for make the team more stronger.