Psychologists like Renee Baillargeon were critical of Piaget's research of cognitive development between the age of 0-2.
According to Baillargeon, it's possible that young babies don't pursue a hidden object simply because the lack the specific motor skills to pursue it.
Baillargeon also argues that babies may not pursue the object because they may lose interest in the hidden object because their selective attention isn't developed enough to stop themselves from becoming distracted.
