Meta description used by Google is wrong

Hi,
I know this is a recurring problem for a lot of people, and it is VERY frustrating: the meta description I’ve written for my homepage isn’t the one used on Google for several of my sites.

I own about 8 WordPress sites so I’ve been able to compare the conditions when it happened or didn’t happen:

– At first, I though it was due to a bug in the Yoast SEO plugin. But I’ve found that the meta description is correct for some of my sites that uses the plugin.
– There is one theme that I have installed on 3 of my sites, and for the 3 sites, a full article is used as the front page (instead of the latest posts), and the rest of the site is set up similarly. For one of those sites, the correct meta description is used (the one I wrote for the front page). For another, a text from a footer widget is used. And for the 3rd one, the 1st half of the meta description used by Google is the start of the meta description I wrote, but then it cuts to some random bullet points used in my article.
– I have 3 other sites which used a similar theme. Two of them have the same layout (same widgets used at the same places) – let’s call it A – and the 3rd one has a slightly modified layout (let’s call it B). For one of the A layout sites, the correct meta description is used, while for the other A layout site, a text from a sidebar widget is used (so the conditions are the same, but the result is different). The site with the B layout doesn’t use the meta description I’ve written, but uses Navigation menu links (which is useless…)
– My only site which uses a “Latest Posts” layout uses the correct meta description I’ve written.

What’s the point of writting a useful (and keyword-rich) meta description if Google doesn’t use it ?
Does anybody have a solution to this problem ? Maybe a plugin that fixes this issue…