How to compare a variable in a FOR command with one outside of the FOR command?

I'm working on a program that's based on a device used in the early 20th century. While testing on parts of the program, a part of the code doesn't work like I thought it would. Here is some code that is similar to it:

@echo off
setlocal enabledelayedexpansion
cls
set /p ar=Type a number:
:loop
for /l %%a in (1,1,100) do (
    set var1=%%a
    if !var1! equ %ar%(
        echo It worked
        goto pause1
    ) else (
        echo It didn't work
    )
)
:pause1
pause

What I'm trying to do here is comparing the "%%a" variable with a variable set outside of the FOR command, but every time I tested the program, it would suddenly exit from the command prompt. I have tried changing the order of the commands, and changing the symbols, but the output is the same. I've checked many references and I haven't found any that tackles this certain scenario. Can you tell me what I'm doing wrong here and what to do to fix it? Thank you.