Today's attributed quote of John Dryden appears below with something more of an attempt to give a citation for the quote.

"Let those find fault whose wit's so very small,
They've need to show that they can think at all;
Errors, like straws, upon the surface flow;
He who would search for pearls, must dive below."

From the prologue of John Dryden's Play All for Love (1678)

Nitpicking is part of discovering better ways?

"Let those find fault whose wit's so very small,
They've need to show that they can think at all;

Your added two first lines to me seem easily separable from the last two lines. Almost like two different quotes. In the first two lines Dryden himself is a fault finder with those who find fault. (those who find fault are not always people who have 'wit so very small'.)

Many things have been developped by some people finding fault or errors. When I see the four lines I think I would need an even larger context to understand Dryden's point.

Everybody knows a turkey

- - The Christmas Song

That is the point of giving full citations. When you realize you want or need more you can then go find the rest from the source.

This is why it is worth taking the time to do the research and provide a full citation if you can, instead of just giving an attribution of the authors name alone.

Offering a quote and then saying it is from X author is next to useless, especially when you are dealing with a prolific writer.

Errors, like straws, upon the surface flow;
He who would search for pearls, must dive below." John Dryden

It's a just a quote, which are most of the time taken out of context. The message is clear, dive for pearls if you feel like it. Didn't bother me till you added the other lines.