Functions reduce performance?

I have a datapack that is extremely laggy, and I want to optimise it. I made a bin folder and am going line by line through the datapack. Any duplication that I find (e.g. execute if score @s example matches 1.. then in the next line execute if scoe @s example matches 1..) I make a new function in the bin folder, run it if example matches 1.., then run whatever the original commands did. I'm wondering if this actually helps, and if calling many functions can actually reduce performance