Preparation is never time wasted.
You cannot have a great recital if you have poor rehearsals. People who don’t want to rehearse can never perform well at the recital. I've met people who want to show up for the performance, but they are absolutely not interested in rehearsing. If you don't have something shiny and exciting for them to do, if they might actually have to find their own drive and inspiration to work on a task, they are not interested.
"I’ll come and eat, but I’m not cooking, and I’m not washing dishes."
But preparation time is never time wasted. There are seasons of our lives, wilderness experiences, tests of preparation, that God will lead all of us into. There is no way past it. All of go through them. For it is in the wilderness where we are shaped and humbled, where we become willing to say,
"I’m ready to learn. I’m ready to submit. I’m ready to enter the process of preparation. I’m ready to be 'proved.'"
The wilderness experience is preparation for times of temptation that will come later on. This is why the Holy Spirit drove Jesus into the wilderness to fast. Deprivation in a wilderness experience prepares you to be able to say "no". Fasting announces to the body: "Body, this is a dress rehearsal. You are not in charge. I can feel your cravings and I resist the response. This is a rehearsal."
The wilderness experience you're going through is a test of prepartion. God is giving you the opportunity to train your body, your emotions, your feelings, and your moods for what is yet to come! His goal is to make you ready, complete, mature, not lacking anything.
"Just because the enemy comes knocking, doesn’t mean he gets to come in!"