Be able to vary your call center size easily and quickly. Have lots of part-time students on call to handle overloads. Get good databases and trouble-tracking systems. Finally, always be prepared for the unexpected. The truth is that the PC hardware and software environments are in a terrible mess.
New software is bug-prone, and the software developers are usually late with upgrades.
There are dozens of modems and even more drivers on the market that are incompatible with each other. RPI modems are cheap and lure unwary customers. Finally, IP stack conflicts are common and users often don't know what they are doing. It may be a jungle out there for providers, but for customers, it should always be a walk in the park. As providers, our success lies in making these problems invisible to the customer.