@echo off
setlocal enabledelayedexpansion
set Timer_Primary_Repeat_Counter_Value=5
set Timer_Primary_Second_Counter_Value=3
set User_Primary_Command="echo Hello world!&echo(&pause"
set Timer_Secondary_Repeat_Counter_Value=%Timer_Primary_Repeat_Counter_Value%
for /l %%x in (1, 1, %Timer_Primary_Repeat_Counter_Value%) do (
echo !Timer_Secondary_Repeat_Counter_Value! repeats remain
set /a Timer_Secondary_Repeat_Counter_Value-=1
timeout /t %Timer_Primary_Second_Counter_Value%
cls
start "" cmd /c !User_Primary_Command!