Ask HN: What is it about 6 weeks?

I noticed a lot of things can get better in 6 weeks. • I had some health issues lately and after 6 weeks of getting my habits under contol I gained back my health. • In email marketing when you want to get back deliverability on gmail or hotmail it usually takes 6 weeks • My newsletter for remote-working parents gained traction after 6 weeks • Kids get their colic after 6 weeks usually • And after 6 more it’s gone Do you have any examples to back it up?