Why edit low-interest 3-year old answered question?

Question

I am not sure I understand editing on Movies SE-section. What is the use of editing old, answered, low-interest questions with minor corrections? I am not currently suggesting to change the current practice, but mainly asking to understand this behaviour as it seems quite common here and to me seems not to be coherent with other features like editing unanswered questions to bring it forward to homepage again.

From help-section: When should I edit posts?

Any time you see a post that needs improvement and are inclined to suggest an edit, you are welcome to do so. The original author of a question or answer may always edit their own post, regardless of reputation level.

Edits are expected to be substantial and to leave the post better than you found it. Common reasons for edits include:

• To fix grammar and spelling mistakes
• To clarify the meaning of the post (without changing that meaning)
• To include additional information only found in comments, so all of the
• information relevant to the post is contained in one place
• To correct minor mistakes or add updates as the post ages
• To add related resources or hyperlinks

I understand the above, but to me it seems as relevance is also criteria, because editing bumps the question-answer into homepage. This is also aim why often questions get edited to get question into front-page, so why edit those that have an answer are low quality and lack wider interest among community? Taking account the age of question I don´t understand the actual use of editing (or old identification movies)? As in example of these below:

1. https://movies.stackexchange.com/questions/10168/identify-movie-with-quote-there-is-a-pattern-to-predict-the-future
2. Identify movie where alien with proboscis/trunk steps on someone's head
3. Movie about fishing family who buy their own boat and end up losing everything

I understand editing in cases where popular questions attract a lot of unwanted answers: What does the Flag symbolize?

Answer 1

Any improvement to a post improves the overall quality of the site. That's why there is a badge specifically for editing old ignored questions. And its the same on every stack.

Answer 2

I noticed that the examples you supplied were my edits. So, I feel compelled to explain to some degree.

• I find this place really fascinating. As a relatively new user, I find myself compelled to read old questions. I find them fascinating, informative, and a great way to express my satisfaction through voting on them. I DON'T care if they are old, short, or not widely followed. I am just grateful that I am able to follow them.

• One of my minor talents is that I am a decent proof reader. Spelling and grammar mistakes jump out at me and bother me in the sense that I actually like correcting them -- if I am allowed to. So, I have been doing so because I think it makes the site look better, and I am giving back to those that post when English is not their first language.

• Please understand that this has little to do with reputation, badges, or anything that is self-serving. If you were able to see my voting patterns, you would notice a very strong tendency of mine to simply reward people that were posting well (by my measure). And yes, I have skimmed all the way to the first post. But now I am closely scanning questions, and reflecting on them. But for me, that also includes leaving it a better place when I leave -- if applicable.

• Actually, I don't consider myself so different from other new users.

• I hope you do not mind too much. I am simply trying to help.

• FYI, I have brought up in chat that I have found English errors in our help section. I was advised to bring this up on Main Meta. And I will. Again, I am just trying to help.