What is a <table>? Is it a content tag, or is it a presentation tag?
Let’s think about how this tag is used. In the case of a multiplication table, it is a content tag. It specifies the inherit structure of the information to be represented. The cell at the intersection or row ‘4’ and column ‘5’ is the product of the two numbers, ‘20’. Another cell of the same row, but intersects at column ‘7’ has a value of ‘28’ because 28 is the product of 4 and 7.
However, designers also use tags for presentation. It is common for designers to use tables for layout control. In this case, the information being presented has no intrinsic table structure.
Consequently, the <table> is used for both content and presentation purposes. This makes it difficult for screen readers to decide what to do with a table. In the case of content that has a table structure, it makes sense to announce the row and column for each cell. In the case of tables used for layout control (presentation), there is no intrinsic relationship between a cell and the top row or left-most column.