Digital Ocean is guilty of this. If you're on a phone, or a tablet, or any browser with a window narrower than about 700px, the page is so obsessed with selling Digital Ocean that in order for an existing customer to use an account you've already paid for, you have to click the hamburger menu, and then scroll... scroll... scroll... all the way down to the bottom of 75 options to find a sign-in button.
For a company that brands itself as being tech-forward and people-friendly, Digital Ocean should know better.