InDesign fractions not always showing as fractions

Why in the image above did it show as a fraction for some but not the other measurement? If I highlight the large 1/4 and mouse over the opentype fraction shows up so I can click on it and change but it doesn't do it automatically like the others. Is this a setting? Or a glitch?
Font: Arial
Opentype Fraction turned OFF. When I turn it on ALL numbers look like fractions.

