In the operation of a business he owns that is notoriously expensive to operate, yet which he has to be prepared to operate in perpetuity, otherwise it's insolvent and it's out of business.
Luckily, as a billionaire, he can well afford those operating costs, especially when they are mitigated by some very nice subsidies (TV money, transfer fees, etc.).
And if the costs are packaged in the form of interest-free loans to himself, there's always the very real chance - if he keeps plugging away, and keeps the business solvent, which he certainly will - that he can get it all back later on, via the sale of the business, or the disposal of player assets, or a dramatic increase in those TV subsidies via league promotion.
Which is why it isn't really a loss.