Such deterioration could be caused by exposure, time or just by ordinary use. Tenants are only liable for negligent, irresponsible or intentional actions that cause damage to the premises. These examples may help to explain the difference.
What does QCAT see as Fair Wear & Tear?
In Griffin v Gini  QCATA 325 Judge Fleur Kingham, Deputy President said:-
 The phrase “wear and tear” has been common in leases and tenancy agreements for centuries (Taylor v Webb  2 KB 283, 302). In general, the ordinary meaning of the phrase is concerned with the consequences of ordinary, not extraordinary damage (JSM Management Pty Ltd v QBE Insurance (Australia) Ltd  VSC 339, ). In the case of “wear”, this might mean, for example, fading paint work on internal and external walls caused by sunlight over time; “tear” refers to disrepair caused by a tenant through unintentional action or through the normal incident of a tenant’s occupation (Taylor v Webb  2 KB 283, 302). Depending on the specifics of the obligations outlined in a tenancy agreement, this might include the accidental ripping of an aged, worn fly screen. In summary, fair wear and tear, in the context of a residential tenancy, refers to damage or disrepair caused or resulting from ordinary use.
 The evidence before the learned Magistrate, about the walls and the bench top, concerned damage that fell outside the scope of fair wear and tear. For example, the Griffins attempted to repair damage to patches of the wall by using paint that did not match the original paint work. The Griffins accepted they had painted the walls but argued the paint they used matched the original. The learned Magistrate concluded the paint did not match. I am not persuaded there was any error in his assessment.
 Although this may have been done by the Griffins in an attempt to rectify damage, applying paint does not fall within the scope of ordinary use. It is a deliberate act; the Griffins have caused damage to the walls through that deliberate act
 There was also evidence of other damage to the walls: blue biro and sticky tape. The use of the latter was specifically prohibited by the terms of the lease and, therefore, falls outside the scope of ordinary use. As for the blue biro, this might well be accepted as fair wear and tear, but the evidence indicates this is not the primary basis upon which the damages claim was based.
 The damage caused to the bench top falls into the same category; deep grooves possibly caused by the use of a knife without a chopping board, cannot be said to fall within the scope of ordinary use.
 Regardless of whether the damage was caused before the sixth and final tenancy commenced in May 2010, or during the period of that tenancy, the Griffins are liable for the damage. They were the only tenants occupying the premises under a tenancy agreement during the time the damage must have occurred. The Ginis would always have had the right to recover damage that fell outside the scope of fair wear and tear. The damage caused to the walls and the bench top does not fall into the category of fair wear and tear and regardless of whether the tenancy in question commenced in 2010 or 2007 the damage was caused by the tenants.
In North South Real Estate & Anor v Kavvadas  QCAT 306,  the Adjudicator said:-
The question of what constitutes ‘fair wear and tear’ often arises in residential tenancy disputes. Generally, it means damage or disrepair of the premises or their fixtures or fittings, caused or resulting from normal use or changes that happen with ageing. The legal meaning attributable to the word ‘wear’ is the deterioration due to use. The word ‘tear’ means the deterioration due to forces of nature. Whilst a tenant will be responsible for negligent, irresponsible or intentional actions that cause damage, the tenant will not be responsible for deterioration caused by ordinary, everyday use or deterioration that occurs as a result of normal exposure to the elements or which naturally occurs over a period of time.