A good abstraction is one that makes it easy to express the solution in a way that the customer wants. A bad abstraction makes it hard. For example, if the cus

A good abstraction is one that makes it easy to express the solution in a way that the customer wants. A bad abstraction makes it hard. For example, if the customer in an end-user and wants a table-like presentation, using an HTML table is a good abstraction. If your customer is a css designer who just wants to see divs, an HTML table may not be a good abstraction.