Back in the day using CVS, and subversion later was a constant struggle. Before switching to git i used darcs for several years and tried mercurial. Git was clearly better than any of them.

So, how can you tell that git is no good, if it is the best of the tools available?

I've used git and mercurial extensively, but only with git have we regularly had the need to summon The Expert. With git I have to tell new users "don't use a flag or setting if you think you know what it does, look it up". That has not been needed for mercurial.

One particular good feature is the concept of a commit phase. It makes is crystal clear when rewriting history is allowed, and more importantly, when it isn't.

"how can you tell that git is no good, if it is the best of the tools available?"

Because the UI is complicated & confusing for new users, making it easy to dig yourself a hole.

It's also inconsistent; "git branch -d" vs "git submodule remove" vs "git tag --delete".

It isn't the best, you just like it best. Lots of people do not agree. I also used darcs and mercurial. I still do use darcs, and have essentially stopped participating in most open source projects because I find git so unpleasant to try to use.

> subversion later was a constant struggle

The only struggle about svn is branching (copy the whole thing) and merging was more frequent. There were many CVS systems, which I worked on, where there was no way to track who made what change in a day.

You switched from using "was" in your first paragraph to "is" in your second. There are certainly more competitors to Git today than there were then.

Are there really more? Some similar projects like Monotone and Bazaar are no longer being actively/regularly developed IIRC, and the number of hosting services for something as well-known as Mercurial has been dwindling.

Because, I'm guessing, a lot of people using Mercurial (like me) are just using GitHub. Mercurial has had a functional bidirectional git-mercurial bridge extension for over half a decade and I've never ran into issues with it.

The result is that I happily keep using Mercurial locally even when collaborating with people using Git. I don't see the need to have Mercurial specific hosting. (Well, until Bitbucket finally starts working with obsolence markers so I can use Changeset Evolution).

To say nothing of the fact that comparing git to svn or cvs is disingenuous; it should be compared against its peers, the fleet of candidates in the distributed source control management (DSCM) space.