Conditional Formatting Rule
Data
I want the value under Total Hours to be highlighted if it is less than the value under Expected Hours for every row.
If the Applies to: is to remain `$E:$E, then the formula should be based on,
=AND(ROW()>1, $E1<$F1)
The additional ROW()>1
condition is actually not needed for your layout as Total Hours is considered greater than Expected Hours but if the column label in E1 started with a letter less than the E in F1's Expected Hours it would actually trigger a false positive.