Why invest in a company that loses lost of money?

Uber is expected to go public (i.e. list its shares on the stock exchange) later this year, where it is expected to be valued at $100 billion or more. Like several other tech companies (Amazon, Netflix, Tesla, etc), Uber is a household name, and has pumped billions of dollars into development for a decade or more in an attempt to establish a dominant position in its market. But it still fails to make a profit, relying on deep-pocketed investors to keep it afloat.
Although investors are often blamed for being too short-term in their outlook, in some cases they seem to be ignoring the short term completely and looking to the future with some optimistically rose-coloured glasses. Uber has consistently made hundreds of millions (up to a billion) of dollars in losses each quarter and, while investors might hope for big profits in the future, they are by no means assured. With similar services like Lyft and DoorDash snapping at their heels, and with any number of court cases limiting their operations in various cities and jurisdictions around the world, or looking to control who Uber uses as drivers and how much they are paid, theirs is still a rather shaky business model.
So, will you be putting a bunch of money into a company that has made huge losses for years? I know I won't.

UPDATE
Uber's main competitor Lyft beat it in the race to go public, and it too sports a grossly overinflated valuation despite its own record of uninterrupted losses. And who said that investors were rational actors....