User-centered design principles tells us that we all go to websites to complete a task. Making it an easy and smooth experience requires lots of solid research and intelligent people trying out things to guide the most users to where they need to go.
This is all ruined if you have to get information by downloading a document. Nothing bums me out more on a website, even on my PC over my cell phone, than clicking on a link and something downloading. I just want the information, I rarely want it in a format where I can print it out and hang it on my wall. Even though I am apparently a rare millennial who owns a printer (mostly for auto insurance cards and scanning in documents for work.)
Put important information, especially directions, right on a webpage. Although with our faster Internet speeds and machines the “three-click rule” is no longer a hard guideline, it’s still a great experience to not have to dive into five different documents for info that could be on just one webpage. Especially on websites that do not indicate what will launch you off onto another website or open up said document instead of just another page.
Unlike those hefty Word docs or PDFs, webpages allow you to control keywords and structure for search engine optimization without diving into menus, are easy to update in one swoop for information version control and are generally (if your website and the page is built correctly) easier for those with disabilities to navigate. Plus, not everyone has access to Microsoft Office Suite or Adobe services or the luxury of their own devices. Building content for those with the least amount of tech toys really helps most people easily access that info.
But how do you know when it put things in documents? Publications that you need digital access to or for people to print on their own. That’s it, in my opinion.
Everything else would be better served directly on a webpage, graphics included.