Trying to redirect a command output to an already existing file will fail
echo "hello" > output
echo "world" > output #file exists: output
cat output # hello
to solve this use >|
to overwrite the file completely
echo "hello" >| output
echo "world" >| output
cat output # world
or use >>
to append to the file
echo "hello" > output
echo "world" >> output
cat output # hello\\nworld
use >>!
to create the file if it doesn't exist initially
echo "hello" >> output # will fail becasue the file doesn't exist
echo "hello" >>! output # will create the file and append to it
cat output # hello