They have good ideas too. And they might figure out a better way to do it. Volunteers are not always present. Bring them up to speed on news and changes. Keeping them informed helps everyone.
Communicating poorly can be a big problem.
If people understand what is expected, they do an effective job. Loyalty and respect. Treat all your volunteers the way you would like to be treated. Your volunteers expect and deserve to have an enjoyable volunteer experience. It should be continuous.