The list of waiting jobs contains jobs that have to be kept on the system for some time. It is not yet known when they should be printed. Jobs in this list are never printed automatically. User intervention is required to send jobs from the list of waiting jobs to the list of scheduled jobs. You can change the job properties in the list of waiting jobs.
As soon as a new job is received in the list of waiting jobs, the job ticket (when present) will be interpreted and the job will be made visible. Spooling continues in parallel.
Printed jobs end up in the list of printed jobs.