Lineups are frustrating. They are barriers that prevent customers from fulfilling necessary and often tedious tasks. That means that if you don't manage your lineups properly, you'll lose business due to customer frustration. Not to mention your staff will be stressed-out.
Most managers think the best way to manage a lineup is to get the staff to work faster.
Often, this only creates worse problems. Consider the impact on your staff of trying to work at full speed. Ditto for the negative impact of working faster on your customers. Only a fool would want tired, aggravated employees interacting with customers. Working faster to get through a line-up cuts short the human interaction that creates customer feelings of loyalty.