Quick answer
Money that arrives fast and crooked tends to leave the same way. Money assembled by hand tends to stay.
Read both lines
The Hebrew of the first line is closer to wealth gained from vapor or emptiness, which covers dishonesty and also covers anything that came from nothing real. Against that the second line describes gathering by hand, a little at a time, and the contrast is about rate as much as method. What the verse observes is that money without a foundation under it behaves like money without a foundation under it, and this is one of the least mystical claims in the book. The same instinct sits behind 11:18's contrast between deceptive work and sowing.
Related: Proverbs 11:18 · Proverbs 20:21 · Proverbs 28:20
New King James Version®, Copyright © 1982, Thomas Nelson. All rights reserved. Full copyright information. Scripture provided by API.Bible.
Go Deeper
If this verse has been used to put weight on you that it was never carrying, ask about it directly.