Ask HN: Why are PDFs so hard to edit?

There's a pretty decent explanation here:

https://mailmergic.com/blog/why-pdf-are-hard-to-edit/

The most compelling tidbit I found was this:

> The Technical Architecture of PDF: A Labyrinth of Objects

> Beneath the surface, PDF files are complex compositions made up of objects: text blocks, images, vectors, fonts, metadata, and instructions for rendering. These elements are often stored in fragmented sequences that are optimized for viewing rather than editing. The text is not always stored in logical reading order, and words may be divided into separate character objects placed precisely on the page based on coordinates.

Lots more there. No more spoilers.