A visual representation of New Keynesian economists trying to make DSGE models fit reality: add a friction, add another friction, add another friction... then take their ball home and quit.
DSGE models begin with highly simplified assumptions about rational individuals, markets, and expectations. When their predictions fail to match reality, economists often introduce new frictions such as sticky prices, sticky wages, adjustment costs, imperfect information, and financial constraints. My critique is that these additions increasingly serve to protect the underlying theory rather than challenge it. After enough modifications, the model risks becoming a collection of patches designed to fit the data while preserving assumptions that may have been flawed from the start.