Did you know that you are an expert at measuring? No really, you are! I guarantee it. Now before you dismiss me as a snake oil seller, here me out.
When you walk up steps, have you unexpectedly tripped on a step? Or have you been to an old stadium, and there's that ONE step that almost everyone trips on?
Do you know why? Because you're an expert at measuring! At least in how high you have to lift your feet on steps.
When you go up a set up steps, your brain gets feedback from your legs, and it knows how high to lift your leg for the next step. Your brain automatically assumes that the height of the first step is the height of the next step. And the next one. That's why when a step is too far out of standard, people trip!
Code is written (at least around these parts) to keep all steps within 3/8" height of each other on the same set of steps because of this human nature. Castles used to make steps uneven as a defense mechanism, to create a disadvantage for anyone not familiar with their uneven heights.
We recently did some work at a house, where the front steps could be considered a defense mechanism. No thief is going to rush up these steps without tripping!
The bottom step was 8 inches high.
The middle steps were somewhere around 7 inches. I say "around" because it was anywhere from just under 7 inches, to over 7-1/2 inches!
If none of those steps didn't get you, don't worry, the top one would! It was a whopping 8-1/2 inches high! Right after a set of "around" 7 inch steps!
Can you say "Face plant"? Very good. I knew you could.