Money now is more valuable than money later.

As someone who has both built and sold software, it's simply to be able to sell software before it's complete. Without estimates, you can't sell something that doesn't exist yet.

This doesn't change the fact that requiring estimates is a bad idea if you want great software. The best software is built well, then sold.[0]

Great software later is more valuable long-term than bad software now.

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[0] The best case is actually to sell software without a timeline. But most organizations are not able to operate this way.