I love grid layouts. It's my favorite type of layouts, and I do intend on using them as much as I can on Cowriters' new website. A few reasons come to mind.
Grids allow you to take some height. They are great to scan a lot of content at once and easier to navigate. If you manage to blend in all the information you need in a grid, you can browse webpages much quicker by pressing the tab key. That's not the case when you have two navigation menus and side panels to go where you want. A grid and a toolbar with a search form are all you need to browse content simply and efficiently.
Full grid layouts taking the whole width are mobile-friendly and responsive by design. You don't have to hide parts of your websites on lower resolutions or distinguish the desktop layout from the mobile one.
Grids done right are aesthetically pleasing. Cards can form patterns and are exciting to look at. Unlike regular lists, they aren't dull to watch and browse. Instagram's profiles and Explore page are a good example of that. Marketing Examples has made it an original characteristic.
A grid forces each element to be short, concise, and impactful, because the width and height of each part are limited. It's a great way to make sure the content is designed for the reader and easy to consume, or ditch when bad content is all too common.
Using a common grid to display a variety of information—the way Nomad List blends in content, calls to action, ads, and announcement—removes unnecessary introductory elements. The reader can just intuitively hop in and go where his curiosity guides him. After all, astonishing content is like wild sex: you have to skip foreplay and get into it. Telling the visitor what to do or providing a lengthy introduction can be a major turn-off: just place the user at the center of the experience right away and give him directions. That's probably the reason why Pornhub is designed with a grid layout.