Note, the certain purposes for some rockets were not the real reason. It was just created to make more sense in the story.
Chapter 1: Three Strikes and You're Out!
The first day at the KSC consisted of the launch of Loki 1, the first craft of the short-lived Loki Program which would be revived later as the main type of emergency capsules. Surprisingly, Jebediah was not the first kerbal to fly a spacecraft; he would be the first kerbal in space, a much larger title. Bob Kerman, once a biologist, took the title of first kerbonaut. He was in 2 out of 3 of the launches for the Loki program, which was made for early testing to create a standard way of launching a rocket. Loki 1 blasted off about 2 minutes after midnight, testing the first legitimate rocket engine. It was recovered 3 minutes later near the shore of the KSC. After only a day of preparation, Loki 2 was already due for launch. It was testing how much gravitational force a kerbal could withstand, with Bob freaking out and eating all his snacks instead of passing out like the scientists had expected. It had 5 engines attached to it, which would decouple and float down to the ground with parachutes.
The last Loki, Loki 3, was just parts of Loki 2 refueled and reattached without 1 booster and the decoupler. It was launched on the same day Loki 2 launched and was the first craft launched by a female kerbal, Rosetta Kerman (Valentina would become the first female kerbal in space, a much larger title.) The reason for Loki 3 was to show female kerbals that they too could be kerbonauts, and to test a new system. Loki 3 was known shortly after it's launch as the Loki Disaster, due to the system accidentally arming all 4 parachutes while the rockets were still firing. The parachutes ripped, and the craft fell like an arrow near the R&D. From then on, the flight director, Gene Kerman, announced that the first space station that the KSP launches, would be named the Rosetta Kerman Space Station. "Poor kerbal didn't even get to munch on the cookies!" one of the founding scientists, Wernher Von Kerman says while eating the cookies from the Loki 3 Capsule, or what was left of the capsule. The staff will be taking a week off at the beach near the space center. Further questioning about the fate of the Loki Program ended in Gene Kerman replying "We are shutting down the Loki Program, but using what we found in it for future missions." before heading to the beach. The president, Joseph Kerman, responded sternly to this, "We will not let disasters like this happen with the Kerbal Space Program. The 10 scientists and their crew we funded need to show us reports of success, not failure."