The Hebrew is `שְׁאוֹל וַאֲבַדּוֹ`, Sheol and Abaddon, the same pairing the NKJV footnotes at 15:11.
Quick answer
The realm of the dead never fills up, and neither does human wanting. The verse compares two appetites and says both are bottomless.
Read both lines
The comparison is grim and precise. Sheol receives everyone and is never described as filling, so the image is of an appetite with no relationship between intake and satisfaction. Then the second line puts the eyes of man in the same category, and the choice of eyes rather than stomach is the craft: eyes are the organ of wanting rather than of consuming, and they can want without limit precisely because they never take anything in.
Ecclesiastes says the same thing without the comparison, that the eye is not satisfied with seeing (1:8), and Proverbs 30 will list the grave among four things that never say "Enough!" The verse is not moralizing about greed. It is describing a mechanism, and the honesty of it is the point: this is not a hunger that gets solved by feeding it.
Why translations differ
The NKJV renders שְׁאוֹל as "Hell" and footnotes Or Sheol, and gives "Destruction" with the note Heb. Abaddon. The catalog's settled position applies here without change: name the translation issue, read the term as the realm of the dead as the ancient text understood it, and teach NO doctrine of final judgment from a proverb in either direction, neither eternal conscious torment nor conditional immortality. This verse is a comparison about appetite. It is not evidence for anyone's eternal destiny, and it is not evidence against any position on the question. The received text also carries a scribal variant in the spelling of Abaddon, which affects nothing.
Related: Proverbs 15:11 · Proverbs 30:15–16 · Ecclesiastes 1:8 · Proverbs 21:16
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.