Why is there a need for Moshiach [closed]

It is said that we dont receive the reward for mitzvot in this world, but in the olam ha-bah. So, if the ultimate reward will be given in the olam ha-ba, why the need for moshiach? If this world is but a testing ground, we will get our reward in the olam ha-emet, no?

So, why this obsession with mashiach? All the past generations have lived their lives without moshiach. Are they in any way defective?

(I have realized that mostly it is the basic factual questions get responses.)

Moshiach isn't about reward. It's about the world becoming the place it was meant to be from the start.

Hashem created this world in order for there to be a dirah b'tachtonim - a place for Him to dwell here below, however the world wasn't ready for that. It's kind of like plugging a high voltage appliance into a low voltage socket. The fuse blows, it's not able to contain the energy.

In order for the world to be able to exist, when Hashem created the world, He made a Tzimtzum. A tzimtzum is like a filter. When you’re in a room with big windows and the sun is shining brightly, it could be very uncomfortable. It could be too hot and too bright, so we have window shades. When the shades are closed, the sun doesn’t disappear; it just makes the rays more bearable.

So, now we’re living in this world where G-dliness is concealed within nature. It’s a physical world. Everything that is tangible or pleasurable, we experience with our five senses. We see it, smell it, feel it, hear it, or taste it.

We learn about G-dliness, but it’s not something we could fully grasp. We’re told that when we do mitzvos, it has an incredible effect on the world, it brings brings more and more G-dliness into the world, making it ready for all His glory to be revealed. But as of yet, we don’t see it. We could only rely on what we’re told and what we learn.

So yes, the past many generations did live, as we currently do, in a world that was defective and they were well aware of it. For many generations, the Jewish people have asked numerous times in their thrice daily prayers for Moshiach to come. Until his arrival, we will continue to do so, and continue to learn Torah and do Mitzvos, preparing the world and bringing down more G-dly light.

When Moshiach comes, G-dliness will be revealed. The window shades will be completely opened, the tzimtzum taken away. When we do mitzvos, we’ll be able to see and feel the effects it will have on the world. And as we say at the end of the Aleinu prayer, "On that day [when Moshiach comes], Hashem is one and His name is one."