Similar to the way a delicate strand of pearls too tightly strung on a strand can buckle and appear out of place, Google may have begun to piece together too many services. Each pearl in the analogy aims to represent another service, from Google Content Network to Nexus One, all strung together by an advertising model (the string.) If the pearls get strung too tightly on the strand, they tend to become crowded and lose their beauty and potential.
Source:Search Marketing Daily: Has Google Strung Its Pearls Of Innovation Too Tightly?
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