Some small fixes in the descriptions of "Letters to Cozy Glow" and how applying them made me get better at something I'm struggling with

So, after I checked into "Letters to Cozy Glow" yesterday while writing the next letter/chapter, my eyes fell on the short description and I discovered a small error in it. Small, as in, only one word was wrong. But it made the sentence sound very stupid and gave a wrong idea of what it says.
I went and fixed it, then read through the long description to make sure there isn't a similar error. I found one and it sounded similarly stupid and I fixed that one as well.
The good thing about that is, that I learned something new while fixing them. As someone who is not an english native speaker, there are a couple of things I'm still getting wrong even after years of writing. One of these things is using the correct word to describe a circumstance or to convey a certain meaning.
It took me a while to find out what I did wrong and what I needed to do in order to fix it with the help of a dictionary, but I figured out the problem with these two sentences and can now tell the difference between these words/phrases:
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But maybe a special team of ponies and creatures could succeed where she and her friends had failed.

But maybe a special team of ponies and creatures could succeed where she and her friends have failed.

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"had" is what I wrote there first. Now I know this was wrong because "had", if put alone without other words added to it, means that Twilight and her friends never tried to teach Cozy Glow about friendship and that their failure would have only happened if they had tried. Another way to say the same thing would be the phrase "would have (failed)".
This was not what I intended to say. What I intended to say was that they indeed failed with teaching Cozy about friendship. "Have" is the correct word to convey this, only this word expresses that the failure happened. So this sentence is fixed now and I now finally grasp the difference between "had" and "have" in a sentence.
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The only catch was that Tartarus' security level had been increased.

The only catch was that Tartarus' security level has been increased.

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Here, I wrote "had" first. Interestingly, the same word as in the short description. This was wrong, because "had been" means that someone does something by themselves. It's an active phrase, referring to it that someone actively does something. Which does not make sense in this context here, because the security level of Tartarus can't do anything by itself. It's not an AI, so it can't increase itself. Even if Tartarus had an AI that operates everything, the security level could still not increase itself. It would then be the AI that increases it.
In both cases, with and without AI, someone else increased the security level. "Has been" is the correct phrase to convey this, it means that something is done with someone by someone else. It's a passive phrase, referring to it that someone is passive while something happens to them that is not caused by them, but instead by another person, an object, a circumstance or an event.
Therefore, only the phrase "has been" expresses that the security level of Tartarus got increased by someone.
This sentence is fixed, too, now and I now finally grasp the difference between "had been" and "has been" in a sentence.
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This is amazing because, usually, small differences like this completely slip past me. I don't even see that I'm doing something wrong and it feels completely right to me. But yesterday, when I looked at the descriptions again, I suddenly sensed that something was wrong. And could go and dig into it until I found the error. This has never happened before and it makes me cheer.
If you are an english native speaker, this might not seem like a big feat to you. But I was and still am someone who learns only very slowly and so, this small thing I learned yesterday and that I can apply these words/phrases correctly from now on is a HUGE thing for me.
Maybe I'm finally starting to figure out all the things I'm still doing wrong when writing in english now.

Comments

[Bronycommander]

Sounds good!