One of the foremost reasons for that is the amount of matches being played with a league consisting of 18 teams. Logistics, accommodation costs, staff expenditure, large playing squad, are taking its tolls on the clubs finances , while revenues from match tickets , sponsorship and TV rights do not reach anywhere near the level of breaking even. Merchandising will never reach the aspiration level of the clubs due to lack of intellectual property laws and copyright violations in Iran. With the government being the main sponsor/proprietor / owner / partner of most of the clubs and seemingly infusing less and less money to the clubs citing its own economical difficulties, the financial troubles are threatening the existence of many established clubs.
The already tight and busy league schedule; are being pressed further by other commitments such as the Cup Competition "Jam Hazfi" and the Asian Champions League which in itself is a major commitment in terms of finances and playing squad. In addition, there is also the international, regional and continental competitions of team Melli at all ages level leading to the league being stopped at times.
Considering all those factors, it seems that the current 18 team league competition is quite demanding and lacking stability. Poorly scheduled, long season and at time, disorganized, many matches in the league become trivial, especially those between the mid table clubs. Many matches that are costing the clubs become meaningless at mid-season stage or even earlier due to the table ranking. Fans lose interest and even the media have little incentive and drive to report on those matches. These sorts of matches leave a heavy burden on the clubs.
Of course, the busy league also affects Team Melli preparation as well with many clubs become reluctant to release their players for friendly matches consequently affecting Team Melli overall standard and preparation.
There are some positive aspects to the current 18 teams’ format but those advantages are over shadowed by their distinct disadvantages.
It is of utmost importance for the IFF and the League management to re-address the number of clubs composition in each league. A Serious financial situation might spell the end of the professional football league as we see it now. An urgent action is required after a careful feasibility study and revision of the clubs resources.
It is one balancing act for the federation to embark on with urgency and well before the start of the new season. Lack of action will mean more players being not paid , more bills by the clubs being over due and loads of court cases and FIFA interventions and possible sanctions.