For some reason technically minded people tend to gravitate to being behind the scenes. We often feel more comfortable running the lights than being the ones standing on stage in front of them. We would rather control the microphone rather than sing into one. We prefer operating a video camera as opposed to being in front of one.
There is nothing wrong with being behind the scenes, and these roles are critically important. But there is a side-effect of this that can often be frustrating. These roles tend to be thankless jobs. The only time someone notices what you do is when you screw something up. If you run a flawless service, the band and pastor all get pats on their backs. If you mess up, then you are the one in the line of fire.
I think one of the worst feelings that a tech director or volunteer can feel is having something go wrong in the middle of a service and then every head swivels around and looks at you. That is horrible. You feel like crawling under the desk and disappearing.
We have each been given certain gifts and abilities from God to use for His glory. Some people have been given the gift of teaching or singing, and they function best when they are in front of people. Others have been gifted in more supportive roles. That does not make them less important.
[2 Timothy 2:20] Now in a wealthy home there are not only gold and silver vessels, but also ones made of wood and of clay, and some are for honorable use, but others for ignoble use.
What you do is so important to the Kingdom of God. Although you may not get a pat on your back every time you do a good job, it is important to know that God sees what you do. At times you may feel invisible, but God is working through you to present the Gospel in a compelling way to many people. Your role is just as important to God as the man or woman who is up on the stage.
At times you may feel like giving up. God's Word encourages us to not grow tired and not give up. You are storing up treasures in heaven. What you do is not in vain. Maybe you made a mistake and feel horrible about it? Do not let that keep you down. Do not give up. God has equipped you with gifts that are useful and necessary to the body of Christ!
[Galatians 6:9] So we must not grow weary in doing good, for in due time we will reap, if we do not give up.
As a tech director it is important to keep yourself encouraged through the truth of God's Word. If you are leading a team of volunteers it is equally important to give them encouragement for a job well-done. Even if your role seems to be unnoticed take the time to show your team that what they do is important and is directly tied into reaching people with the Good News.