Part 2/9:
During the Apollo era and throughout the late 20th century, rockets were essentially single-use vehicles. Once launched, they were discarded, making each mission a costly endeavor. This approach was rooted in how rockets were designed and operated, with no viable method for recovery or reuse at the time. As a result, spaceflight remained an expensive and infrequent activity, primarily serving governmental and military purposes rather than commercial endeavors.