[bacon_waffle]

> It it goes wrong, you cannot buy a new one or hire repairperson at a sane price. If it has a software side, it will probably need maintainence.

It's not clear to me that the alternative provides these either. Just thinking about some of the appliance-type things I've had issues with lately: my oven would've made more sense to replace than hire a repair person, and my ISP-provided router is running their latest firmware which is horribly out of date...

[eternityforest]

Yeah, but your ISP router does work, and you could replace it if it didn't. Oven repair might be expensive but it's possible (Usually, some places you might have to wait a month, like I did when the heater went out), and not that expensive.

With DIY stuff, sometimes you can't replace it because there's no equivalent, you've invented novel functionality, and bought other things that depend on it.

Like, one time, when I had a very different mindset, I made a controllable light that used a non-DMX protocol, and took power over XT60. I don't know where the special USB adapter for it is.

If "Number of direct dependents" and "Total of all dependents that are in some way customized" are more than just a few, then it's pretty nice to have standard stuff.

Building things that are effectively clones of what you could just buy isn't that interesting to me, but making novel things comes with future unpredictability.

I like to look for projects where there either just isn't any commercial thing at any reasonable price that would work, or the thing is non-critical, or there aren't many design decisions in other things based on the custom thing I'm doing.

[bacon_waffle]

I think that's shifting the goalposts a bit - one can buy weird proprietary stuff from a company or product line that disappears, or build stuff that uses standard interfaces.