I agree that it's more complicated than that! Maybe for any 0.1% of change in the interest rate or inflation rate there is a marginal effect. But eventually q

I agree that it's more complicated than that! Maybe for any 0.1% of change in the interest rate or inflation rate there is a marginal effect. But eventually quantitative differences become qualitative ones. When the interest rate you pay is 4%, the inflation rate is 2% and the interest that you earn is 0.25% quantitative changes become qualitative ones at numbers that seem very innocuous.