I've responded to the related Phabricator ticket with my thoughts and summarization from this thread.

Feel free to keep responding here if you're not too much of a Phab person, I've already linked this thread there. Here's a copy of the response:


**About constructive buttons: **
used to indicate an action that creates something rather than modifying
provide hint that something will be created, regardless of steps
several people have mentioned that green constructive that doesn’t “create” anything


**Constructive vs. progressive buttons**

@isarra mentioned: "If it's shown to help, that's all we need. We have a justification for the maintenance overhead and stuff." Unfortunately we do not have proper resources to help us figure this out. But the current situation is that we've had confusions from developers and community members in understanding when and where to use constructive vs. progressive. For our users to learn the association of constructive button being the last action in a process and progressive being the in-betweens, it "requires [the pattern] to be applied consistently to work" as @pginer-wmf mentioned. Also, in certain complex processes, it's hard to tell which would be the last step. An example given by @tgr was:

"…after you submit the login form and MediaWiki verifies your credentials, depending on your user settings you might or might not be presented with a two-factor challenge; so submitting the user name and password might or might not be the last step of the form."

The idea of constructive vs. progressive sounds like an aid for going through a multi-step process. Its underlying purpose is to keep users informed of where they are within a process. My thoughts are that this progressive/constructive solution sounds like it stemmed from the user need of "knowing where I'm at within a process/workflow."

We can solve this more effectively. @volker_e linked us to a discussion on SO where a user mentioned: "Apple hardly ever uses Wizards for set-up processes, and when they do, the Apple set-up assistants are (in my opinion) always easier to figure out than the Microsoft equivalents. I'd suggest looking at the differences and try to identify the tricks employed by Apple." I can agree with this—a better form /workflow experience.

There is also a good amount of rationale as to why we wouldn't need this sort of variation, which mainly stated complications in applications by the community members and devs and that we have no resources in place to find out if the variation complication outweighs the advantages.

@spage suggested that we use "Green for Thanks, because in an unfriendly often toxic "community" it's a nice Constructive thing to do."


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My suggestion after these observations are:


**BLUE**

The main reasons why we use blue button is to (in order of importance):

(1) Help users with clear step to move forward within a page / workflow (if there is only one way to move on)
(2) To suggest and highlight (if there are multiple options to move on). If no specific suggestion, they remain uncolored.


Example of (1):
Primary actions

Example of (2):
Log-in form
Others



**GREEN**

There are also a few reasons why we would use green for links or icons

(1) To signal that an action has been taken only when it helps users navigate a page / workflow
(2) To highlight a suggested action although not the main action (secondary) on the page or workflow


Examples of (1) & (2):
Secondary actions



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Because more colors means more confusion than help, we should have restrictions such as

Only one color type of button(s) per page / workflow. Either a blue or red.
Never a colored link / icon next to a colored button. Remember, colored buttons are to help users move forward, more colored links / icons dilute the intention.
Use green links and icons minimally. Highlight most important only and only when necessary to help users.


Overall, I'm still skeptical that we can make this a binary decision. I think there's only not-so-good and good decisions. Good judgement is the most effective. That is why guides are there to help someone make the best informed decisions while giving space for creativity.

The most immediate example that comes to mind is the log in form. Both are possible ways of moving forward and both are equally primary actions. But say, as a team, we want to drive more sign ups, so instead of highlighting both, we highlight only one. It's possible that both are highlighted, but not recommended because when everything is in focus, nothing is in focus, but this is a less extreme example of that).
In the other example of blue, one can use blue buttons repeatedly because there is much content around a call-to-action button that warrants a need for focus.

In conclusion, let's retire the idea of constructive and progressive. Instead, we have primary (blue), secondary (green), and destructive (red).

Help me poke holes in my thoughts with more use cases or perhaps strengthen them with more examples and better guides.

mm