Stale coffee

I’ve heard about coffee getting stale over time. And here I am, returning after 10 days of vacation, and deciding to make a couple of flat whites from the beans I had left in the hopper.
First two shots ran at 3 bar. That’s for a coffee that usually runs at 7-9 bars. Only after purging the coffee, putting the beans from the bag and pulling another shot or two the pressure recovered.
Needless to say, I didn’t feel the need to taste the result of 3-bar coffee.