Dwarf Fortress Bug Tracker - Dwarf Fortress
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0001829Dwarf FortressDwarf Mode -- Skills and Professionspublic2010-05-10 16:062010-09-15 14:54
Toady One 
resolvedno change required 
0001829: Dwarf skills decrease rapidly without use.
My dwarfs skills seem to decrease rapidly without use. I had several near-legendary dwarfs of various professions who have minimal skill levels after a few years of unuse.
decay, skills
has duplicate 0002635resolved Logical2u Medical skills rusting very fast. 
related to 0000803resolved Toady One Civilian jobs don't use attributes, so civilians all get weak over time 
Issue History
2010-05-10 16:06BeeskeeNew Issue
2010-05-10 16:07BeeskeeNote Added: 0006516
2010-05-10 16:40MalicusNote Added: 0006518
2010-05-10 18:07FootkerchiefRelationship addedrelated to 0000803
2010-05-10 21:50BeeskeeNote Added: 0006537
2010-06-04 14:28albatrossNote Added: 0007676
2010-06-04 16:50NabeshinIssue Monitored: Nabeshin
2010-06-30 08:05Hieronymous AlloyIssue Monitored: Hieronymous Alloy
2010-06-30 08:05smjjamesIssue Monitored: smjjames
2010-06-30 08:11ThrelicusIssue Monitored: Threlicus
2010-06-30 09:04hyndisNote Added: 0009372
2010-07-07 02:09alexleonIssue Monitored: alexleon
2010-07-11 09:55ProfligateIssue Monitored: Profligate
2010-07-11 15:05Logical2uRelationship addedparent of 0002635
2010-07-12 05:27cephaloNote Added: 0010020
2010-07-12 06:45TomiTapioTag Attached: decoration
2010-07-12 06:45TomiTapioTag Attached: skills
2010-07-12 06:45TomiTapioTag Detached: decoration
2010-07-12 06:55TomiTapioTag Attached: decay
2010-07-12 12:16cephaloNote Edited: 0010020bug_revision_view_page.php?bugnote_id=0010020#r3892
2010-07-12 15:43Logical2uRelationship replacedhas duplicate 0002635
2010-07-12 15:43Logical2uIssue Monitored: Logical2u
2010-07-14 08:58Toady OneNote Added: 0010239
2010-07-14 08:58Toady OneStatusnew => resolved
2010-07-14 08:58Toady OneFixed in Version => 0.31.11
2010-07-14 08:58Toady OneResolutionopen => no change required
2010-07-14 08:58Toady OneAssigned To => Toady One
2010-07-14 09:00smjjamesIssue End Monitor: smjjames
2010-07-15 19:34Logical2uIssue End Monitor: Logical2u
2010-07-19 11:22FootkerchiefNote Added: 0010659
2010-07-20 12:58Hieronymous AlloyIssue End Monitor: Hieronymous Alloy
2010-07-21 09:07ProfligateIssue End Monitor: Profligate
2010-07-25 05:05alexleonIssue End Monitor: alexleon
2010-07-26 05:38ThrelicusIssue End Monitor: Threlicus
2010-09-15 14:54NabeshinIssue End Monitor: Nabeshin

2010-05-10 16:07   
I searched for skills and skill before posting this and didn't see a similar issue, though I may have missed it. If so, sorry. :)
2010-05-10 16:40   
I'm told that stats seem to rot far too quickly, too. Maybe these two things are related?
2010-05-10 21:50   
Possibly. It could also lead to other things such as slower skill/stat gain if the decrease is almost as fast as the increase.
2010-06-04 14:28   
(Rambling follows, bear with me)

Yes. Skills AND attributes (strength, memory, etc.) decay over time. This is by design. However, there's nothing you can do about it. No amount of raw-file editing will help. See the issue 0000803. Rumor has it that physical attributes CAN increase through military training. Everything else (attributes) just goes down over time, no matter what you assign them to do.

Skills: increase and decrease over time
Attributes: only decrease over time, never increase (with few possible exceptions)

Now, I don't know if there's a link between attribute scores and skill gain rates, but if there is, the consequences are pretty serious, improvement-wise. I mean, if a dwarf with higher Memory remembers stuff longer than the other dwarves, and since Memory is an attribute and it can only go down... you probably see where this goes. In short, your dwarves might lose skills at an increasing rate over time, as well as gain skills at an ever slower rate over time (assuming attribute scores affect skill gain/decay rates)

I suppose that to fix this, Toady would need to place a limit on how much a dwarf can forget, and then actually make the attributes umm increasable? I wouldn't mind getting actual control over the gain/decay rates through raw-file editing either.
2010-06-30 09:04   
If attributes were linked to be improved with skills this shouldn't be an issue. Right now you can have a dwarf who is legendary+5 in a dozen different skills and still have the minimum attributes possible for a dwarf. Slow, weak, frail, confused, stupid. :(
2010-07-12 05:27   
(edited on: 2010-07-12 12:16)
Skill rusting sounds realistic in theory, but gameplay wise it just means that you have more chores to remember to make sure your armorer makes one metal cap per year, ad nauseum for each profession.

Furthermore, professions differ greatly regarding how much labor is needed for gameplay. How often do you need a clothier? Never? How often do you need a blacksmith? Once in ten years? How do I prevent my medical dwarves from losing skills? Injure people on purpose?

Skill rusting can cause problems, while the only gameplay solution for skill rust is busy work. Why not just pretend that dwarves keep their skills up in other ways?

Toady One   
2010-07-14 08:58   
I let it sit for a year, and it's still working about like I expect -- a Master miner accumulated 4 levels of rust and no permanent demotion (and wasn't slated for a single level demotion for another 3 years). The rust was worked off after mining 4 walls. For a similar craftsdwarf, I think it would be a few crafted items of somewhat lower quality before being back at peak performance, maybe just one. If I remember, 'v' wasn't showing rust at all in 0.31.03, so I'm not sure where you were seeing the lower values (unless it was in the noble screen or the military screen, where rust was being subtracted). I'm going to change the display in 'v' a bit to separate the rust out, which should make the (rare) permanent demotions more clear.
2010-07-19 11:22   
Reminder sent to: Toady One

Hey Toady -- cephalo's note at 0002635:0010657 mentions that the medical professions are disproportionately affected by skill rust, due to the difficulty of training dwarves in those skills. I don't know whether that moves this report into "bug" territory for you.