What was Ted Friedman's “accumulative advantage" in chapter five?

Ted Friedman became a highly successful lawyer, establishing an impressive record as a litigator in the 1970s.
Ted grew up poor in the Bronx, New York, in a Jewish immigrant family. Ted started college in New York but finished in Ann Arbor. He had a combination of free tuition, low tuition, scholarships, and wage labor to support him through school.
Ted was born in the 1930s and was ready to work and go to college by about 1950. He became an adult during the post–World War II boom years in the United States. There was a lot of employment available to make all the goods the consumers were buying. In addition, there was a lot of investment in public education. The New York public schools were excellent. And Ted could have gone to City College for free, as it had zero tuition.
Gladwell argues that a key advantage for Ted was that his generation was small. The Depression reduced family size, so by the time the postwar boom hit, companies were scrambling for workers. Ted's main accumulative advantage was when he was born.
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