Confused about the usage of bad_source.

From reading the wiki for the tag bad_source, I can understand how it would need to be used when the source doesn't point to the source of the image (in this case the original Twitter posts), such as with post #4421169, post #4427064 and post #4349963, but I don't understand why it's being added when a post has a source link that directs to the Twitter post, such as with post #4531318, post #4454103, and post #4520281.

The images in the latter case have the same dimensions and nearly (difference of one kB), or exactly the same file size when downloaded. Is this because Danbooru doesn't say it's a 100% similarity when in the upload page, is it because the tagger believes this isn't the true source and wants a second check, or is it just human error?

I apologize if making this forum post is redundant, and thank you for taking the time to read it/reply.

A lot of posts with raw source of the type "twitter/i/web/status/" have that tag, it seems they were automatically tagged as such. That doesn't make much sense to me, given that those links still point to the correct tweet. I'll remove the tag from those posts.

I guess it also has to do a lot with old posts, where the art remains in Danbooru, but the Pixiv post is long deleted, or the Twitter account has been suspended long ago.

No, for deleted art we have bad id. bad source is basically for active links that point anywhere but the source.

Oh ok. Thanks for clearing that out.

Davicii said:

post #4427064

Since when artist twitter or /media has been a valid source? Shouldn't the source direct to the tweet itself or by very least to the picture?

It's not, that's what bad source is for.

Tomzai said:

Since when artist twitter or /media has been a valid source? Shouldn't the source direct to the tweet itself or by very least to the picture?

As said above, it's not, nor did I state it to be a valid source. I said I understood how bad_source was to be used in the first three posts I had linked.

Edit: I have since changed the source for the first post to properly link to the image, so it no longer applies, but I feel it doesn't matter since nonamethanks already answered my question.