YES. Oil and gas wells are a depleting asset. Every oil and gas well will most likely be plugged and abandoned. So, although royalty income can increase in the short term due to rises in oil and gas prices or production enhancement projects, your royalty checks will decline over the long run. Each month that your wells produce, there is less oil and gas left in the ground. Selling your royalty income may allow you to make other investments that grow overtime, versus deplete.