Google Calendar's design principles

Fast, visually appealing, and joyous to use
Drop-dead simple to get information into the calendar
More than boxes on a screen (reminders, invitations, etc.)
Easy to share so you can see your whole life in one place

Help needed for "Google Calendar's design principles"!

The following is missing from this set of principles:

Overview: e.g.

overview: This set of principles is designed to promote inclusivity and accessibility. This is achieved by…

Source:A link to the principles or an article about them e.g.

source: http://example.com

Summary: Each design principle can have a brief summary, these could be a couple of lines or a detailed paragraph outlining how this principle is used or measured, e.g.

- principle: Strive to be universal
summary: Our aim is to be a resource that is helpful to everyone. We do this by strictly adhering to principles of progressive enhancement…

It would be great if you could contribute and update this set of principles with anything that's missing!

Fast, visually appealing, and joyous to use

Drop-dead simple to get information into the calendar

More than boxes on a screen (reminders, invitations, etc.)

Easy to share so you can see your whole life in one place