Aṇḍa kukkuṭa nyāyaḥ (hen and her eggs)
Farmer hypothesized that inside his hen must be large amount of eggs, because she lays eggs daily. He decided to cut her open, and take all the eggs at once.
Due to greed a man actually loses. This can be seen in many spheres of today's society, in food production, industry, health care, education, etc. Fruits of one's labor comes in due course of time, when they fructify, according to God's laws, which is supervised and directed by paramātmā. The impatient man tries to speed up the harvest of enjoyable fruits. Instead of that he is getting unripe and bitter fruitage, which naturally causes many troubles. Indeed, this example of rip open hen may seem obsolete and brutal. But millions and millions of hens and other animals are killed daily for the satisfaction of the gluttony of men. If they so stand that they have to subsist on the meat then let them wait till the animals die natural way. Thus they create no grief, and incur no future horrible karma.
Same logic applies to the spiritual practice. There is plenitude of greedy spiritual practitioners, who instead patiently following prescribed process of God realization, offer some shortcut cheap cheating method for quick result, ending up with bitter bowl of fruits. Rather in gaining some spiritual benefit, bogus gurus and their bogus followers, end up in huge spiritual debt.
There are few proverbs regarding the impatience: “A little impatience will spoil great plan” or “Haste makes waste.”