Enlighten me oppo: why are early 2000s BMW 745s so ludicrously cheap?

I mean specifically: gimme the top 5 reasons.

Obviously it’s an old, high mileage German luxury car with a million pieces that will go wrong and I’m assuming all of these cars need way more repairs than they are worth just to get through inspection/emissions to get back on the road.

That said if the powertrain even sort of worked given what parts cost for these things you could have a ridiculous Lemons contender just from selling the seats and wheels...

Or as I posited elsewhere a safari/battle car for rallycross!

But sadly I’m guessing there’s some kind of terminal engine/transmission/computer cancer that makes them worth roughly what my (admittedly functional) '06 focus was.