Have I understood correctly? - Drupal Slider\carousel modules Why in Drupal, so much is needed just to insert a picture into a slider?...

I understand that in the typical Drupal slider modules, we can't just upload a picture into the slider - We MUST choose from and existing photo in the site and it MUST also be an existing photo from an existing View... This is (allegedly) a problem because it forces one to upload the picture to somewhere in the site even if there is no such necessity and also forces him to use Views even if he has no need to.

Why all of this way just to use a picture and are there really no shorter ways to do image sliding in Drupal?

Please correct me if I was wrong in anything here.
There are a lot of options within Drupal. This is it's great strength, but comes with a steep learning curve for starters.

So there are a lot of modules to build a slider. Most sliders require a content type where you upload the image and views to make the list of images. This is not to make it hard, but to give you options on what to do with it.

If you want an 'instant' slider, check out https://www.drupal.org/project/content_glider. No views required.