Economics & market laws · law 030
Law of Diminishing Returns
By Shivam Bhandari · Reviewed 31 October 2026 · How we write
what it means
Adding more of one input while others stay fixed eventually produces smaller and smaller increases in output.
How Law of Diminishing Returns works
The first extra worker in a crowded kitchen helps a lot; the fifth gets in the way. The same applies to ad spend, discounts, features, and hours worked.
The key is to find the point where the next rupee or hour returns less than it costs — and redirect it elsewhere.
where it comes from
Discussed by economists including Anne-Robert-Jacques Turgot, Thomas Malthus, and David Ricardo in the 18th and early 19th centuries, originally about adding labour to a fixed plot of farmland.
Law of Diminishing Returns examples in business
Ad spend
Doubling a campaign's budget brings far fewer than double the leads, as the cheapest audiences are used up first.
Staffing
Adding a fourth billing clerk to a small office barely raises output because the bottleneck is approvals.
Discounts
Going from 10% to 20% off lifts sales a lot; going from 40% to 50% adds little and destroys margin.
How to apply it
- 1Measure the extra output from each additional unit of input, not just the total.
- 2Stop increasing an input when its extra return falls below its cost.
- 3Look for the fixed constraint causing the slowdown and invest there.
- 4Rebalance spending across channels where returns are still high.
common misreading
It does not mean more input is useless — it means the gain per unit shrinks, so balance matters.
ask yourself
Where are you adding more of the same input and getting less back each time?
put it into practice
Frequently asked questions
What is Law of Diminishing Returns?
Adding more of one input while others stay fixed eventually produces smaller and smaller increases in output. The first extra worker in a crowded kitchen helps a lot; the fifth gets in the way. The same applies to ad spend, discounts, features, and hours worked.
Who came up with Law of Diminishing Returns?
Discussed by economists including Anne-Robert-Jacques Turgot, Thomas Malthus, and David Ricardo in the 18th and early 19th centuries, originally about adding labour to a fixed plot of farmland.
How do you apply Law of Diminishing Returns in business?
1. Measure the extra output from each additional unit of input, not just the total. 2. Stop increasing an input when its extra return falls below its cost. 3. Look for the fixed constraint causing the slowdown and invest there. 4. Rebalance spending across channels where returns are still high.
What is a common misunderstanding of Law of Diminishing Returns?
It does not mean more input is useless — it means the gain per unit shrinks, so balance matters.