A common example is contributing too much to a Roth IRA based on your income level; the ability to contribute to a Roth IRA begins to phase out at higher income levels. Contribution limits decrease once your Modified Adjusted Gross Income (MAGI) rises above $105,000 for single filers and $167,000 for joint tax filers.
(A high rate of return, of course, will beat that, but you'll have to work for it.) Assume that inflation is an annual 3% and capital gains are 15%. If your target is a 15% return before inflation and taxes, you'll end up with 12.4% return. (If you pay 20% in capital gains taxes, you'll end up with 11.6% return.) A really good return on investment for an active investor is 15% annually. That's healthy.
What is Internal Rate of Return. In the language of finance, internal rate of return is the discount rate (or the firm's cost of capital, that forces the present value of the cash inflows of the project to equal the initial investment which is equivalent to forcing the net present value of the project to equal $0. Pretty confusing.