Good observation, and another example of the ridiculousness of this whole WU thing…
Setting a thing’s slug should only cost the same as any other ‘make changes to a thing action’ (precisely 0.5 WU).
I just ran some tests and confirmed that this is the case - but only when doing a search for the thing to change directly in the workflow.
i.e. the workflow has a single action to set a thing’s slug - the thing in question being a search for Users: random item.
It consistently costs 0.8 WU to do this, which is exactly what is expected (0.3 WU for the search, and 0.5 WU to change the thing)
I wanted to test this another way, so I then loaded the User onto the page first in a group (datasource, search for Users random item), and then in the workflow changed to to set the things slug , that thing being the Group’s User.
I expected to see that the workflow now only cost 0.5 WU (for the set slug action) as no additional search is needed (the User is already loaded into the group), so you would expect a reduction in WU cost.
But in fact, the workflow now costs now costs 0.93 WU to run - so significantly more when it should cost less. That makes no sense at all. And that’s on top of the search and data retrieval for the User on the page in the first place - so effectively getting charged for the same
I’ve observed in many instances that we’re getting charged multiple times for the same data, especially when it’s relating to data that should already be on the page - I’m not sure if Bubble are doing this type of thing deliberately to increase revenue, or (more likely in my opinion) they just don’t understand how WUs are being calculated themselves (which definitely seems to be the case, based on some discussions I’ve had with their support).
In any case, it’s completely inconsistent with what you would expect from reading the docs, or following any kind of logic.
The only real way to make any sense of it is just to test everything and trust your own observations, rather than taking anything as given from the Bubble docs.
The conclusion here is to never refer to existing data, but always use a new search expression wherever you need to deal with data - which is completely the opposite of what you would think logically, but the data is very clear on this for anyone to check.