Good enough in practice is orders of magnitude better than great in theory.

"In practice" means that it is viable; it works in the real world.

The hard part in practice is not greatness, it's viability.

It's easy to imagine a "great" idea that works only in your mind.

"It's perfect inside my head"

But what matters is what exists in the world.

If it's perfect in your head but you can't make it exist in the real world maybe the idea isn't actually viable?

Greatness is hard to retrofit to an idea; greatness is more about fundamentals.

A general strategy: pick a thing that could be great, and try to get it to viability cheaply and quickly.

These things that could be great are things I often refer to as seeds.

Keep iterating until you find one that is viable and starts growing.