What are some of the reasons why strategy evaluation is becoming increasingly difficult with the passage of time?

What will be an ideal response?

Possible answers include: Domestic and world economies were more stable in years past; product life cycles were longer; product development cycles were longer; technological advancement was slower; change occurred less frequently; there were fewer competitors; foreign companies were generally weak; and there were more regulated industries. Other reasons include the following trends: a dramatic increase in the environment's complexity; the increasing difficulty of predicting the future with accuracy; the increasing number of variables; the rapid rate of obsolescence of even the best plans; the increase in the number of both domestic and world events affecting organizations; and the decreasing time span for which planning can be done with any degree of certainty.