A genuine bug in IRIX 5.3 cost me about 3 days' worth of work 2
weeks ago. Another IRIX bug, or perhaps simply misfeature, causes
my deconvolution program to run up to 30 times slower than usual,
depending on the input. I don't know of any typos in any commercial
UNIX OS, just bugs & features that end up hindering me.
Linux kernel typos generally cost me about
20 minutes to find a fix then the time it takes to do a partial
kernel compile. I admit, its a lot less, but its still a cost.
This cost is incurred by anyone compiling that kernel under a bad
configuration, assuming they try to fix it. Otherwise they just
lose the time they spent patching and partially compiling the kernel.