So you don’t want to take up page real estate to actually display the description of a product when you can just have the description display as a “tool tip” when the user hovers over the image of the item. That is a good idea if your users only access your web site from a computer with a mouse. After a little research I found this note on the W3Schools page about using the Title attribute:

Relying on the title attribute is currently discouraged as many user agents do not expose the attribute in an accessible manner as required by this specification (e.g. requiring a pointing device such as a mouse to cause a tooltip to apear, which excludes keyboard-only users and touch-only users, such as anyone with a modern phone or tablet).

With the rise in web usage from devices without a pointing device such as cell phones and tablets, it isn’t wise to hide essential information from a fast growing part of your potential visitors.