The classical Arps shapes are exponential, hyperbolic, and harmonic. They describe the decline that was observed. They are not a reservoir model, and they do not know why the rate fell.
A fit made while a well was beaned back, or before a workover, does not carry over after that constraint is removed. Changing the choke, the lift method, or the number of wells on a pad changes the curve. The method is most trustworthy when the operating conditions of the forecast match the conditions of the history.