tl:dr
-RAM management
-Omnibar
-Auto update
-Security
-Chrome flags
I remember I switched to Chrome a few months after it was released. I was 100000% tired of Firefox's poor RAM management. The more tabs you opened the more RAM it was using and when you closed tabs the RAM usage didn't drop. Then came Chrome. When you closed a tab it released the memory. Amazing! It was only after years that I realized it was even more incredible that each tab was its own instance when I accidentally dragged a tab out and it turned into its own window and when you drag the window back into a multi-tab window it becomes a tab. Incredibly intuitive design. The omnibox was another massive innovation. Before you had a search box and a URL bar. Google was genius to put all into one, it's a more intuitive solution. Can't remember a website? Just type the name and it turns into a Google search query. The other massive innovation that people forget was Chrome auto-update. The browser would just update itself. A huge convenience. Remember back then you always had to download a new version of the browser from the website and then install, click the admin elevation away and click the adware away and be careful that you don't wipe your old bookmarks and settings etc. and then set it as your default browser again. Chrome just updated in the background, you close it, you open, it's on a new version and you kept all your settings. So by default I installed it on all of my parents' computers years ago. I install it on any old person's computer for those 3 reasons. RAM management, omnibar, auto-update. That's a lot of questions I will avoid in the future. I don't have to worry if they will be on the latest version, I don't have to explain to them how to find a website, I don't have to worry that it slows them down.
For me personally those things have fallen into the background and now I appreciate its security and performance. It's not as fast as Edge and Firefox out of the box but with the right Chrome flags it's faster than all of them. And Google Project Zero is an incredibly bright team that also provides patches for Chrome. What more would I want than a browser that gets patches from that team?