One of the things that struck me reading the letters of some of the fallen soldiers [meant to be read in the case of their deaths] was the lack of mention of Olam Haba. I am not here to judge them and don't know what they were actually thinking.
But it must be said that our entire purpose here is to get to Olam Haba. Not in order to please ourselves but b/c the will of the Creator is that we should live a much more elevated, spiritual existence. We are not doing mitzvos in order to get Olam Haba. We do mitzvos b/c that is the רצון השם. It is also the רצון השם that we get Olam Haba for our mitzvos. This is just a waiting room where we have to take advantage of every second creating a connection between ourselves and Hashem so that we can live for eternity in the bliss of connection w/ Him.
Even though most observant Jews believe this, I am often astounded by how little this knowledge impacts their daily life.
If there is one thing I envy, it is the Olam Haba of people who consciously risked their lives to protect Am Yisrael in Eretz Yisrael. All of the money in the world is ooooohhhhhhhh sooooo temporal, but Olam Haba is eternal. No comparison. And those guys with the heavy money - shhhhh secret - have loads of problems and are often not happy. Jeff Bezos is divorced. Bill Gates is divorced. Elon Musk is divorced [and has big, big problems with his children - besides having Asperger's, PTSD and quite likely bipolar disorder]. I wouldn't get divorced for all of the money in the world - if only for the harm and pain it causes the children. These rich guys have lots of other problems, too. So all of that money is really not the solution to life's problems.
But Olam Haba? Ahhhhhhhhhhhhhhhhhhhhhhh - unimaginable bliss. What our souls need and want and why we are here earning it.