Quick answer
Two sources of light and only one keeps burning. The verse says nothing about brightness, only about duration.
Read both lines
The images are chosen carefully. The righteous have "light," an open and unbounded thing that the verse says rejoices, an odd and warm verb for illumination. The wicked have a "lamp," which is a manufactured object with a fuel supply, and it goes out. That contrast does the work: one is a condition and the other is a device, and devices run down. The book returns to the extinguished lamp elsewhere, and it never means a person was snuffed out arbitrarily. It means the fuel was finite from the start.
Related: Proverbs 20:20 · Proverbs 24:20 · Proverbs 4:18
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.