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So what's wrong with weeds? At least two things:

• They compete with veggies for limited moisture, nutrients, and eventually sunlight,
• AND they are quite capable of perpetuating themselves.

Locally adapted weeds are perfectly adapted to these two goals - they grow rapidly and they propagate profusely.

A lot of weeds propagate by going to seed and spreading those seeds on the nearby ground.

But it isn't minor issue that many weeds also propagate via rhizomes, stolons, and root segments that remain in the soil even when most of the weed is extracted. For more see more information about weeds

I have a choice to allow weeds to grow and diminish harvests or attack them from the time they sprout. When I see a sprouting weed I go into attack mode.

I answer this question with a resounding, “Yes!” Regular weeding that doesn't disturb the lower part of the soil can yield a garden - after a number of passes - that has very few moisture sucking, seed bearing weeds. I am surprised by the middle of the gardening season how few weeds are sprouting.

Not only have I drawn down the seed bank, I have apprehended the villains before they have a chance to multiply. And in the long run, (say five to seven years) I will have very little action from the seed bank vault.

I have seen this most dramatically in a small raised bed. Regular weeding has kept the number of weed sprouts to a handful in a month. At this point it is very easy to keep the bed completely clear of weeds.