It is not hard to understand the appeal of entrepreneurs to wealth managers, especially those owned by large banks: the business whizzes of today—or a decent enough proportion of them at least—will be the multimillionaires of tomorrow. And not only will they need help managing that wealth, they may also require commercial banking services for their companies. If those companies get big enough, they might even be persuaded to pay for some expensive investment-banking advice.

But does it make sense for the entrepreneurs themselves? Are there merits in having your personal wealth management and business banking handled under one roof or should you look, as with your investment portfolio, to diversify? An increasing number of successful entrepreneurs are making a conscious decision to keep their personal and business banking separate, despite the best efforts of private banks to convince them otherwise.