This is also known as the 80-20 rule or "the vital few and the trivial many".
Borrowed from Wikipedia:
"In business
The distribution shows up in several different aspects relevant to entrepreneurs and business managers. For example:
80% of your profits come from 20% of your customers
80% of your complaints come from 20% of your customers
80% of your profits come from 20% of the time you spend
80% of your sales come from 20% of your products
80% of your sales are made by 20% of your sales staff[9]
Therefore, many businesses have an easy access to dramatic improvements in profitability by focusing on the most effective areas and eliminating, ignoring, automating, delegating or re-training the rest, as appropriate."
What are your thoughts on this way of viewing the business model for lan centers? Does it still apply? I think if you can show the top 20% of your customer base makes up 80% of your profit that means it is true. It also works inversely that the bottom 20% of your customers cause 80% of the problems then there is the 60% of the muddle middle that don't cost you anything but are they spending enough to actually matter?
If you can remove, hinder, or stop the bottom 20% from causing as many issues then your business should improve and the problems you experience regularly should appear less often?
I'm not sure if this is a proven fact or just an ideal based on averages, but it would certainly help if you can focus your resources on that top 20% thus improving and increasing your bottom line.