The brilliant evolutionary scientist Stephen Jay Gould once developed this concept to describe how evolution occurred. Before Gould, everyone thought that evolution occurred gradually with time. As time passes by, species break off, forming new species, as you see with the graph below:
Looking at the fossil records, however, Gould realized that speciation isn't a gradual process. Rather it follows a process that he called punctuated equilibrium. This means that evolution doesn't occur gradually; rather, relatively little change occurs in the life of a species except in relatively short windows of time. Here's what that looks like:
I mention this because this process is very similar to how success occurs in life. One rarely becomes successful by gradually working one's way up the ladder.
Rather, one alternates between long periods of skill-building and maintenance, research, preparation, and short periods of outward success, fame, attention, etc.
Those who survive the long, drudge periods are rewarded with opportunities for dramatically increasing their success.
The point here is twofold. First, to be successful, you have to work hard and expect no returns for long periods of time.
Second, you can't simply work hard for long periods of time. You have to look for opportunities to dramatically change your situation. Rarely will your hard work pay off in a gradual way; your hard work is simply preparation for taking advantage of huge opportunities in a short window of time.