Inconsistent data : This becomes most apparent when trying to find a particular record or cell, based on the contents. If a space is incorrectly added in the wrong place, the search or filter fails.
Early databases available for the PC market were simple two-dimensional solutions and were essentially designed as a record-keeping system. However, when computing power increased, the advent of the relational database became an affordable option. Applying the rules proposed by Edgar Codd, the Database Management System (DBMS) became a reality, with products such as dBase being widely implemented in the desktop market.
Protection of formulae : How often have you forgotten to protect the cell contains the formula that took you hours to test and perfect. It takes one instance of honest human error, and that formula is gone.
These are the pros and cons of selling spreadsheets. The real beauty in this idea is that you could do the work once and there is no limit to how much you can earn, especially with effective use of the internet and other mass communication tools.