Google offers the user exactly what they want right away and uses the hamburger menu for less important elements. With the navigation buttons hidden away in the hamburger menu, the user’s attention will be more focused on the primary task.
Uber wields the hamburger button for this purpose. The app has one goal to order car. So the main screen is singularly focused on booking you a vehicle.
For things like records of your past trips, receipts, and payment settings, you’ll have to click on the hamburger menu—since they’re not as important to the primary goal.
The WCAG which stand's for Web Content Accessibility Guidelines Working Group set's the accessibility rules. WAI updates Techniques for WCAG 2 and understanding WCAG 2 periodically.
In this document it talks about how the hamburger menus have diferernt locations or ways to web developer uses it.