It was a bright sunny day. We noticed something amiss in somebody else's post. We thought, "Let's be helpful, and fix it."
So we set our hand to (gasp) editing it. We thereupon see:
Your edit will be placed in a queue until it is peer reviewed.
We welcome edits that make the post easier to understand and more valuable for readers. Because community members review edits, please try to make the post substantially better than how you found it, for example, by fixing grammar or adding additional resources and hyperlinks.
Okay, but it forgot something:
Edits must be at least 6 characters.
Make sure you mention that before users get started!
Mention it right below the rest.
Don't think "It's no big deal. We'll only mention it if the problem occurs!"
I think all the rules are great. As long as you make them clear before people get started.
As far as discussion about these rules please see
What's the logic behind the six character edit requirement?
Why should edits be at least six non-space characters?
Increase the character limit of the custom edit rejection reasons
But those posts are off topic for this post of mine.
This post of mine merely is saying you need to warn users before they get started.
Don't tell them later. They need to know before they get started. That way they wouldn't waste their time, for the supposed marginal case where they only want to change a little instead of a lot.
For instance, as I type this I see below the words
Tags Add up to 5 tags to describe what your question is about
That's good. It's telling them the maximum before they get started.
Therefore you also need to tell people about the above minimums too!