It makes it easier to divvy up into groups: halves, thirds, quarters, sixths (vs. just halves and fifths). Makes doing math easier in the head (fewer digits, checking for divisibility are the big ones).
Also, on the practical level, I have a specific mark to go to for 1/4". 1/4cm involves me guestimating the middle between two mm marks and just deciding that that’s middle enough. Small errors like this can actually add up really fast in something like woodworking
Wait now, why would this matter? Decimal doesn’t need full factors?
It makes it easier to divvy up into groups: halves, thirds, quarters, sixths (vs. just halves and fifths). Makes doing math easier in the head (fewer digits, checking for divisibility are the big ones).
Some info (warning: they are trying to convince you it is better than decimal, so you are not going to get a balanced argument there): https://dozenal.org/drupal/sites_bck/default/files/DSA-DozenalFAQs_0.pdf
Also, on the practical level, I have a specific mark to go to for 1/4". 1/4cm involves me guestimating the middle between two mm marks and just deciding that that’s middle enough. Small errors like this can actually add up really fast in something like woodworking