The Time Machine is so concerned with the theme of time that "time" is in the title. (And it's so concerned with time that the novel's other themes are all tied up with this one.) The time in The Time Machine isn't last week or next year – that's time on a human scale. Time in The Time Machine is on a scale that's totally beyond anything human. This is geological or even cosmic time. When the Time Traveller jumps into the future, he doesn't watch the lifespan of a person, but the lifespan of a species – or even the lifespan of a star. Thinking about time in this way involves looking at the long view – even though that long view moves people out of the spotlight.
The Time Machine encourages the reader to see all human action as useless, because nothing lasts forever.
According to The Time Machine, the past and future are ultimately unknowable because the person doing the observing carries with him too many ideas from the present.