Sometimes, not many words are necessary, and a short and concise message does the trick. This isn’t one of these cases. We feel like some crucial information is missing from this sign, mostly, what does the “no” refer to? What aren’t we allowed to do? Drivers should focus on the road, not try to solve confusing traffic riddles.
We can assume this strangely ambiguous sign is either referring to the height limit or saying there’s no entrance to this lane, but we really can’t be sure. I guess the safest thing to do is just refrain from doing anything – whatever you’re about to do, don’t do it, that way, you can’t be wrong.