In Pikmin 1, Olimar blasts off in his S.S. Dolphin every night. Before the player reaches the screen detailing changes in Pikmin population and part count, he comes to a journal entry. These journals are Olimar's notes on the nature of the Pikmin Planet, and are often written in an inquisitive manner. Often, they regard obvious things to the player (i.e. Pikmin development, the 100 Pikmin rule, bomb-rocks). Those of 'value' would be those that have detailed analysis on a creature, or those regarding his life on Hocotate, as these have information that the player does not know.
They reveal a lots of facts about Olimar's private life, his job, his likes and dislikes and his family. Especially in the last few days, the log-entries start to become more melancholical and despaired, since Olimar is knowing, which fate is awaiting him, if he doesn't manage to collect enough ship-parts soon. He starts having nightmares and becomes completely homesick. Among the very last entries, Olimar can write, there's a very interesting example: He states, that he sometimes wishes to be a Pikmin himself, to escape some of the pressure he got at home. The tone of this entry suddenly changes, when Olimar starts writing in Capitals, like he was screaming to himself, since he realized, that he just wished for a life without his family. This entry seems to be hinting the worst ending, the player can get in the game: Olimar dying and being changed into a Pikmin by a Red Onion.