My experience is the opposite. Most of the staunch Mercurial supporters came from CVS or SVN and found Mercurial to fit better into their preexisting mental model of source control.
Users that started with Git are more likely to internalize Git's concepts as "the natural way to do version control", and more likely to find Mercurial counterintuitive.
Not my experience. As it happens, Mercurial and Git are very similar in terms of the "mental model" required to use them: history is just a DAG, and common operations consist of navigating the history and creating/editing/re-organizing commits.
But where mercurial shines with a clean, consistent and simple UX, git is a mess where storage-layer abstractions leak to the user and where single commands serve multiple unrelated purposes.
To give you a practical example, any command that takes commit(s) as argument (for checking-out, logging, rebasing, …) would be passed a `revset` in mercurial-land. Revsets are a simple DSL to address commits (by hash, lineage, topology, distance, …), which makes new commands easy to learn, and renders one third of `git help log` inadequate. Most commands that output something use templates as argument, which renders another half of `git help log` laughable.
There is nothing "natural" about the git UX, you've got to accept that it grew organically with no attention to details.
I really love git for the way it has taught me so many things by being so exposed. I love that you can easily use it as p2p, via email as a server or client, as a ci/cd solution. I love that you can easily inspect its model with cat. I love that while “branches” and “tags” seem special, you could just as easily use its “notes” or even just tack on your own ref system willy-nilly.
All this to say, I love git, and as a versioning system, it seems obvious to me that we can do better than git for 90% of workflows. Just yesterday I was surprised by how `git push --tags` worked and had to read the man page for `git-push` to see I wanted `git push --follow-tags`. Just reading this forum today I see that I alternately probably(?) could have figured out what I wanted with `git help push` which I didn’t even really realize was a thing.
But do I want to use an easier versioning system? I’m not sure. git has a kind of forcing function for a growth mindset. I value it for its creative expressivity.
Edit for sibling comment: Stockholm Syndrome, quite possibly. But as the “victim,” I still love git!
heh, I'm highly sympathetic of what you say :) . I also got to use git after being told how awesome it was, by people who themselves were told how awesome it was, and so on and so forth. And for many years, I was a believer, too, and probably heightened the bar of what I found acceptable as a result.
That's not to downplay git qualities, but as a social experiment in soft peer-pressure and group-thinking, I think it has value (though that's beyond my field of expertise).
I came to mercurial when, after shooting myself in the foot with git for the N-th time and going on a rant about it, someone on IRC told me to give mercurial a shot and move on with my life. I confess that TortoiseHG helped me translate my git habits into the equivalent hg commands, and the kind of history exploration that I was doing then set me up to speed with the revset way.
Then, what I found formidable was that all the knowledge about git intricacies that I had accrued and internalized with pride over the years became absolute no-brainers and irrelevant in the hg world: I remember a famous stackoverflow thread in 10 steps for merging two unrelated repos (including arcane git commands, shelling-out to sed, and non-transactional storage-level ops that would warrant a backup, as was the norm back then). How do you get history from a repo in hg? `hg pull`. How would you go about getting history from a repo (unrelated) in hg? `hg pull` as well. And thinking about it, would have git been nicely designed, it wouldn't have had to care about the difference and even less so had to expose it to the user.
Mercurial, although not perfect, really opened my eyes on what good UX design should look like.
People don't internalize Git concepts as "natural", they get Stockholm Syndrome.
I'm not saying mercurial is better, but there's a reason I have to remind people that this[1] is satire - the real manuals are so convoluted that they seem like parodies of themselves.
There are two reasons Git is better, and the UI is NOT one of them: speed and repository format. I think Keith Packard wrote about this best: Git is technically under the covers way superior over Hg, it's not even a competition. For usability, I think with Sapling we finally get some real competition and that might be the user interface alternative we need, as well as the monorepo approach it was basically made for, but let's just say that I don't trust people who think Mercurial is technically even close to a good idea.
Users that started with Git are more likely to internalize Git's concepts as "the natural way to do version control", and more likely to find Mercurial counterintuitive.