with other crafts it often tells you why: that's the best you could do given the tools and the materials, or it was your tools not your skills, or you can't make good from bad.
But I looked back through my living characters (all of whom have been alive for many versions) and all it says is
You fail to maintain the quality of the superior clean elk-skin during this step.
You fail to maintain the quality of the superior clean black grouse-skin during this step.
But among my dead characters, several of them go to the superior rinsed skin step, and only one of them fails to maintain the quality of the rinsed skin, so I'm guessing (but don't want to carefully read through these old files) the others got superior furs:
grep -aE "superior.*rinsed" */msglog.txt
0/msglog.txt:(3C5A98):hchi:[:]{02610659} | You pick up the superior winter rinsed arctic fox-skin.
5/msglog.txt:(3C5A98):88hj:[:]{03C40682} | You pick up the superior rinsed elk-skin.
5/msglog.txt:(A80000):98h3:[!]{03C40682} | You fail to maintain the quality of the superior rinsed elk-skin during this step.
5/msglog.txt:(143270):4ahj:[#]{03C30683} | You see a superior rinsed capercaillie-skin (being prepared) here.
5/msglog.txt:(3C5A98):4ahk:[:]{03C30683} | You pick up the superior rinsed capercaillie-skin.
5/msglog.txt:(3C5A98):kchn:[:]{03C40682} | You pick up the superior rinsed raven-skin.
5/msglog.txt:(3C5A98):kchn:[:]{03C40682} | You drop the superior rinsed raven-skin.
5/msglog.txt:(3C5A98):kchn:[:]{03C40682} | You pick up the superior rinsed raven-skin.
5/msglog.txt:(143270):e1ig:[#]{0292071C} | You see a superior rinsed black grouse-skin (being prepared) here.
5/msglog.txt:(143270):e1ih:[#]{0292071C} | You see a superior rinsed black grouse-skin here.
5/msglog.txt:(3C5A98):e1ih:[:]{0292071C} | You pick up the superior rinsed black grouse-skin.
5/msglog.txt:(3C5A98):e1ih:[:]{0292071B} | You drop the superior rinsed black grouse-skin.
5/msglog.txt:(3C5A98):e1ii:[:]{0292071B} | You pick up the superior rinsed black grouse-skin.
5/msglog.txt:(3C5A98):gbjb:[:]{07A00597} | You pick up the superior winter rinsed elk-skin.
43/msglog.txt:(143270):j7id:[#]{06060066} | You see a superior rinsed hare-skin here.
43/msglog.txt:(3C5A98):j7id:[:]{06060066} | You pick up the superior rinsed hare-skin.
43/msglog.txt:(3C5A98):j7id:[:]{06080061} | You drop the superior rinsed hare-skin.
43/msglog.txt:(3C5A98):j7id:[:]{06080061} | You pick up the superior rinsed hare-skin.
43/msglog.txt:(143270):g8i9:[#]{06070061} | You see a superior rinsed fox-skin (being prepared) here.
43/msglog.txt:(143270):g8i9:[#]{06070061} | You see a superior rinsed fox-skin (being prepared) here.
43/msglog.txt:(143270):g8ij:[#]{06070061} | You see a superior rinsed fox-skin here.
43/msglog.txt:(3C5A98):g8ij:[:]{06070061} | You pick up the superior rinsed fox-skin.
the 0 character, Dearsu, died in April 2022, the 5 character, Behtter, died in December 2022, and the 43 character, Pekka, died in August 2022, but these were all long living characters, and I can see from other files that they were migrated from 3.70, so it's impossible to say what version these results were in, except that it was definitely before 3.72, and what we really want to know is whether superior furs are possible in 3.85.