From sona pona, the Toki Pona wiki

The tenseless approach avoids forcing speakers of such languages to adjust to a new piece of grammar. It also opens some expressive possibilities, for example:

  • Leaving out time information to specify that something is true regardless of timeframe. In English, there is no such general tense. "A leap year happens every four years." uses present tense, regardless of whether a leap year does happen to land on this year. "Gravity is a fundamental force." could be mistaken for a temporary statement—"How long until it won't be anymore?" Toki Pona simply lets time information be omitted in such cases.
  • Leaving out time information for other reasons, like if you don't know when something happens (or did, or will), or if such information is a secret.
  • Reducing redundancy when the timeframe is already obvious from context. This is significant as time phrases tend to be several words and syllables long, and thus would get repetitive. In terms of Toki Pona's philosophy, it also encourages speakers to be mindful.
  • Generalizing a statement that happens at multiple points in time; inductive reasoning.
  • Emphasizing or reiterating the time when it's important to a specific utterance.