This paper examines the interactions between entry size, growth rate, and probability of survival of firm. Standard microeconomics states that firm growth stems from relative efficiency differentials and that growth positively affects the likelihood of survival. Therefore, the selection hypothesis is unable to explain how a wide number of small newly born firms can survive at length even without growth and how an even larger set of firms with a higher than average growth rate exits the market in the first few years after the foundation. It is shown that one way out of these apparent paradoxes is to relax the hypothesis of a one-to-one link between initial relative efficiency and survival, and then develop a model based on different entry modes and growth patterns of the newly born firms.