Question: Lately I have been visiting some Stack Exchange sites like Italian Language and similar, and I saw a lot of people (moderators included) tend to comment chatty things like “Welcome to ...”. I know it’s friendly, nice and whatever, but isn’t it against the rules? When I first registered on Stack Exchange, I only used Stack Overflow and I always got downvoted/had my questions closed/etc., for less important things.

Plus, they even ask/answer weird things that on [more serious websites](https://stackoverflow.com) don’t exist (if not for just a few minutes) or, if they do, they get downvoted.

There they even get upvoted by a few people (probably just because the ones asking them have a lot of reputation or something) and it’s really confusing seeing this kind of difference between those websites. I love Stack Exchange because, unlike all other Q&A websites, it is constantly being controlled, so you only find quality content; but I think those uncontrolled (or controlled by a few people) communities tend to ruin this brilliant web site.

So my main question is: why do moderators, the ones that more than anybody else should know how to use this website, make such errors?

Answer: 
Small communities, especially ones still in beta, are different.

All Stack Exchange sites exist primarily to build a repository of knowledge on a particular topic. We want to build a library of well-asked questions with good, solid answers. That's why the focus is on Q&A and not forum-style chit-chat.

*However*, small communities need to grow, sometimes one user at a time, and especially when the topic is relatively "niche". While Stack Overflow is large enough that it isn't negatively affected by a bunch of users coming once, getting an answer, leaving, and never returning, on smaller sites "never returning" is a lost opportunity. We want to convert passersby into engaged users -- or, at least, the ones who want to help build that Q&A library.

And because the [easiest way to drive off a new user is to ignore the person](https://meta.stackexchange.com/a/167510/162102), experienced users on small sites (whether "regular" community members or moderators) leave what are *technically* chatty comments to welcome and guide the new user. These comments usually get deleted after a while, at least if moderators notice or people flag, but the people on the small sites I'm active on see these comments as helpful or at worst harmless.
If you think a comment is too chatty then you can always flag it as such.

If your flag gets declined and, on reflection, you still think that it is clearly too chatty, then you could re-flag, but a better alternative may be to post into the Meta of that site to see whether your views echo or are at odds with the rest of that community.

Personally, I like to see no chatty comments on sites because the Tour says, I think on all sites, that there should be no chit-chat.