Trade-offs between organismal traits are among the strongest constraints on life strategies for most species and individuals (MacArthur and Wilson 1967; Grime 2006). The balance between offspring quantity and quality is a classic example found in many organisms.
In humans, these trade-offs can be complex. For example, an individual either has muscles to run fast, but for a short period of time, or (s)he is able to run for longer at a slower pace, exhibiting one of two alternative strategies to escape predators.
This basically implies that famous heroes such as Superman or Homer Simpson (i.e. with strategies corresponding to “never” vs “always” being caught by predators) are actually quite difficult to find in nature.