Having a minimal employee can hurt the entire operation. Realizing this is important when difficult decisions need to be made. Understand that most businesses cannot shut down as they reorganize or redesign. The rule here is 'don't shoot yourself in the foot'. Usually this means don't fire or lay-off until you have replacements.
Minimal employees are usually cheaper but deliver much less value.
Review your staffing at least once a week. Go through each employee and determine his or her appropriateness for the business. I like to use a spreadsheet, keep notes and strategies current so they can be constantly reviewed. I 'star' those employees that are 'on the bubble' or are delivering questionable value. Do evaluations and reviews every three months.