Nike's Corporate Brand Logo Evolution

Nike probably got the best deal amongst all companies when Caroline Davidson designed its logo for just $35 in 1971. The main part of the logo hasn’t really changed with time. However, I don’t understand why they waited for 7 years before they realized that the text and the swoosh were overlapping each other.
As the brand gained recognition, the company name was dropped from the logo, which made it more simplistic and memorable. The company has different variations of this logo for its various departments like Skate, Soccer etc.