Why an Unbalanced Fan?

Hi,
The fan shown below supposedly came from a 345 in a Loadstar. Why are they made so unbalanced with blades placed so unevenly? I've always understood IH v8's were totally internally balanced unlike some engines that required engine-related balanced vibration dampeners etc. Aftermarket flex fans have their blades evenly spaced. Wouldn't the bearings in the water pump last longer with a balanced fan? Just curious.

The fan is balanced even though it may not look like that.
Answer this. How will any person be able to match an unbalanced fan to an engine when that fan is V-belt driven? There is no way to index any V-belt driven accessory.
What ever the fan, it is very important to have a fan shroud. The fan should be spaced properly with 75% inside the shroud and 25% outside the shroud, toward the engine.

The fan is balanced even though it may not look like that.
Answer this. How will any person be able to match an unbalanced fan to an engine when that fan is V-belt driven? There is no way to index any V-belt driven accessory.
What ever the fan, it is very important to have a fan shroud. The fan should be spaced properly with 75% inside the shroud and 25% outside the shroud, toward the engine.

Yes I agree with the fan shroud. But that fan just looks so unbalanced. What is the advantage to having the blades so unequally placed around the hub compared to the fan below, for example? It's hard to believe that fan is going to run as smooth as this fan below. And this fan comes from a Cummins engine which I assume is a slightly lower rpm engine than a 345. Yet this fan looks better balanced than the fan above.

My best guess is for noise reduction. The uneven pattern may have broken up the harmonic wave or signal whose frequency is an integral (whole number) multiple of the frequency of the same reference signal or wave.
While IHC built simple trucks, I have to think they did some testing of components before these bits and pieces were released for sale.
My R120 had a 9 blade fan. under full pull it could almost raise the dead.

Nikki nailed it, sound. Esp when the number of blades exceed 4. Even on4 blade fan they are not evenly spaced.