So with every transaction that happens on the market (for example lets say someone is selling logo design services for $100 worth of PDL tokens) There will be a fee with each transactions, so if in this case there is also a $10 PDL fee, a portion of that fee will burn the token forever. This means supply is being reduced over time and value is going up.
On top of this we are also burning 1 billion of the 9.5 billion supply throughout the first two years.