Add HP quote.

README.md

@@ -31,6 +31,7 @@
 * [Drive: The surprising truth about what motivates us](https://www.youtube.com/watch?v=u6XAPnuFjJc)
 * [As a product manager...how do you earn the respect and trust of your team?](https://twitter.com/johncutlefish/status/1124938723093766144)
 * [Teams are like bread](https://blog.jessitron.com/2019/06/15/teams-are-like-bread/) - `If you have one team where the magic is flourishing, don’t kill it. Feed it, grow it, and let it be a source of further strong teams. No rushing.`
+* `Over the years we have developed the policy that it is important for the supervisor to thoroughly know and understand the work of his group.` ([source](https://news.ycombinator.com/item?id=20683609)). From [The HP Way: How Bill Hewlett and I Built Our Company](https://www.amazon.fr/dp/0060845791).
 
 
 ## Cross Team Dynamics