In a batch group, the execution path consists of a series of one or more levels that are executed in sequence.
A level is a collection of one or more batch jobs.
If a level contains multiple batch jobs, then these batch jobs are executed in parallel.
If a level contains only a single batch job, then this batch job is executed singly.
All batch jobs in the level must complete before the batch group proceeds to the next task in the sequence.
Because all of the batch jobs in a level are executed in parallel, none of the batch jobs in the same level should have any dependencies. For example, the Stage and Load jobs for a base object should be in separate levels that are executed in the proper sequence.