Why did Microsoft Remove these Windows Features

Over the years Windows has had many interesting features, but a lot of them have been removed and never seen again. My goal here is to investigate what happened to them.

Timestamps:
0:00 Intro
0:07 People Bar
1:11 Windows Maps
1:38 Dev Home
2:20 Mail & Calendar
3:00 Cortana
3:26 WordPad
4:02 Trying Cortana, Mail, Maps
4:53 Windows Timeline
5:19 Honorable mention
5:58 Outro