When you purchase a timeshare, you are buying an object for personal or family pleasure.  It's not an valued investment like real estate.  Unlike real estate property or valuable jewelery a timeshare has no resale value.  Contrary to what the salesman says, a timeshares value does not increase over time.

A timeshares value, is a matter of perspective to it's owner.  Travel and vacation memories may have more worth than any amount of money for some people.  The timeshare can be thought of a luxury item.  However, if you looking to gain equity from this timeshare purchase, you'll be very disappointed.

When you purchase a timeshare, you do not own land or property.  Instead, you own space for a specific moment in "time".  A bank will not accept a timeshare as collateral for a loan,  it wants something physical with monetary value that can be seized if the loan defaults. 

Seriously, think about it.  The concept of owning a moment in time does sound pretty absurd.