frustrating

As I mentioned, this can be not only frustrating, but also lead to contamination of the system.

Whenever I have a truly bad day, frustrating as it may be, it's a matter of time until my next smile.

This was one of the most frustrating moments of my life.

If you’ve ever taken a shower with low water pressure, you know how frustrating it can be, because you just can’t get enough water out of tap.