I saw this article about the top ten table tennis blades. I found it strange that they included Yasaka Ma Lin Carbon on the list. That was probably the worst blade I've ever tested. Absolutly terrible blade with terrible feeling. Here is a link to the article:
https://pingsunday.com/top-10-table-tennis-blades-excellent-quality/#comment-4798
What is the worst blade you've ever tried?
Ma Lin carbon is not that bad. It is just a slow carbon.
The worst blade was a Juic Chinese penhold blade, rated ALL+, about 20 years ago when Paddle Palace was promoting Juic brand hard in the US. I don't remember the name. I properly purposefully lost that blade about 2 weeks into owning it. That blade was sooooo slow. Every ball I hit went into the net. That was before internet was that popular. I felt....cheated. And the blade was pretty expensive for my college student budget back then.
Now, we have all these forums to seek opinion. I really cannot think of any terrible blades.
I am also a big believer in, at the minimum, OFF- 5-ply wood blade even for beginners. I do not recommend ALL+ blades to anyone. For beginners, you can put a slow, thinner sponge rubber on that 5-ply wood blade to start with. A slow blade, well, that's kiss of death right there.