Were you taught debugging

[GCDEF]

This list is pure nonsense.

For example why is a debugger better than the rest?

All the methods you suggested
Debugger
Log File
Event log
Trace output
Message box

with the exception of the debugger, require you to modify your code specifically for the purpose of debugging. That in itself aside from being messy and time consuming can alter the behavior of the program.

Among other things., the debugger lets you watch your program run step by step. It lets you view and jump around in the call stack and examine the local variables at any point in the stack. It lets you watch variable assignments as they occur in real time or even change the value of variables while the program is running. It lets you see return values from functions and values of arguments passed into functions. It lets you watch variables or memory locations and break when they change. It lets you modify your code and continue execution right where you left off.