Of course not everyone speaks English fluently, and everyone who can communicate their question should be allowed to ask a question on here.
However, sometimes there is a question or post which seems to have very little effort put into the grammar/spelling, and is written with such poor English that I cannot decipher what the question is trying to ask.
For example, in this question, the OP has made no effort to capitalise when appropriate, and is even inconsistent in their spelling of "cal"/"call". When I hover over the downvote button, this is the tooltip:
This question does not show any research effort; it is unclear or not useful
According to these criteria, this post is absolutely worthy of a downvote. The OP has made very little effort in writing the post itself, let alone researching their topic. The content of the question itself isn't bad, the but I want to discourage such poor quality standards of questions on the site.
A less clear-cut example is this question. In this case, I think the OP has made a genuine effort to communicate their question, but has failed. I cannot edit their question to clarify, as it's unclear what they're asking. Is this worthy of downvoting if the OP doesn't bother to clarify by answering the questions in the comments? I'm not sure. Again, I don't want to encourage posts which are unclear; heck, there's a close flag for that.
In many cases, these questions are left in the aether, initially hoping that the OP will eventually clarify, and eventually forgotten. I think we should avoid accumulating such questions on the site, so why not downvote them early and retract these downvotes when the OP clarifies?
What is the consensus/policy/convention on handling questions which are unclear due to a language barrier?