Wesco was not just a smaller, equally good version of Berkshire -- each dollar of its book value was plainly worth less, and the gap was widening in Berkshire's favor.

Warren Buffett's business partner and vice chairman of Berkshire Hathaway

Wesco is not an equally-good-but-smaller version of Berkshire Hathaway, better because its small size makes growth easier. Instead, each dollar of book value at Wesco continues plainly to provide much less intrinsic value than a similar dollar of book value at Berkshire Hathaway.