> Companies buying those machines need years to get their money back. If they didn't believe they would make a good ROI they wouldn't buy as much.

In the late-1990s companies were building out fibre optic networks, as they believed they would get a lot of ROI from all the Information Superhighway demand. The expected demand never came in the expected timeline.

Of course demand eventually used up all the dark fibre over the course of many moons, just not quickly enough to save many companies:

* https://en.wikipedia.org/wiki/Telecoms_crash

The only company making AI chips, and allowed to buy from ASML, is TSMC, otherwise it's probably memory manufacturers.

Even if the order book is mostly TSMC, it doesn't necessarily mean the demand is mostly driven by AI (although maybe it is) - there are plenty of other high volume TSMC customers like Apple, AMD, Intel, Qualcomm, Broadcom ...

Finally, just because lots of TSMC customers may have made forward commitments (or whatever it takes for TSMC to commit to expansion), the main conclusion would seem to be that they needed to do that for business continuity given current capacity constraints. It's not clear why the need for them to do this should be taken as a sign that the AI datacenter bubble won't pop. Do you want to be Apple and gamble that rather then locking in TSMC capacity now you can gamble on the bubble popping and maybe get better terms later?

As a counterpoint to this "no need to worry" story, CoreWeave's 5 yr bonds are now yielding 15% ...

And incidentally, believing that you can keep making a good ROI even if it's not true is what fuels a bubble.

ASML sell photolithography machines, which presumably can be used for many kinds of chips: CPUs, GPUs, flash, RAM, etc...

They don't need to be AI chips, so even if the AI bubble bursts before they managed to get a ROI, they can switch to other applications that need high end electronics, such as PCs and smartphones, maybe cars.

> Companies buying those machines need years to get their money back. If they didn't believe they would make a good ROI they wouldn't buy as much.

But if they're in FOMO mode, they might not be thinking about ROI at all. Or if they're in bubble-optimist mode, they would just assume their ROI will be good.