The completion of the U.S. government's stress test isn't an "all clear" signal to bank chief executives whose institutions continue to struggle.

Regulators have said as much, and analysts and lawyers firmly believe that, in particular, banks that require capital from the government would have to go through management or board changes, or both.

The changes may not come about as humiliating public dismissals; no current banker makes a good poster boy for the financial crisis in the same way that former General Motors Corp. (GM) Chief Executive Rick Wagoner represented the auto company's and industry's ills.

But bank regulators can demand, and have demanded, chief executive dismissals by the sheer power of their oversight. Such drastic action requires tangible catalysts - violations of regulations, for example, a sudden and severe drop in deposits, or a lack of security and risk controls. Bad management alone is traditionally not sufficient reason for regulators to remove a chief executive.

Bank regulators have in the past shown a deliberate approach rather than sudden action. Take Commerce Bancorp Inc., the bank that sold itself in 2008 to Toronto-Dominion Bank (TD): Its founder, Chairman and Chief Executive Vernon Hill was removed via public regulatory order after years of concerns about the involvement of his family in providing paid services such as branch design to the New Jersey bank.

Such corporate governance issues may get revisited. Federal Deposit Insurance Corp. Chairman Sheila Bair said last week that her agency, in concert with the Federal Reserve, will be "reviewing capital plans and corporate governance structures."

Analysts and lawyers believe that at least for now, the threat of management action mainly stems from the need for government support. Banks, big or small, that are forced to tap "Treasury for either additional capital or to convert existing [Troubled Asset Relief Program] preferred into common stocks or convertible preferreds are at risk of seeing the government ask for a change in the board and the executive management team," said Jeff Davis, director of research, Howe Barnes Hoefer & Arnett Inc.

Treasury Secretary Timothy Geithner said the department "will evaluate whether existing board and management are strong enough to restore the firm to viability without government assistance." According to the Wall Street Journal, regulators have put pressure on Bank of America Corp. (BAC) to change its board.

But Geithner told reporters that the government would seek management changes only in "extraordinary" circumstances, where it takes a significant ownership position. Pressed by reporters to define significant, he said: "Significant is significant. We do not want to be in the day-to-day management of these institutions."

White House spokesman Robert Gibbs reiterated that position Friday.

"I assume those regulators also will make determinations about not just the suitability of those plans" that bankers are submitting to improve capital following the Federal Reserve's stress test, "but whether or not the corporate leadership of those institutions is right in instituting what has to happen in those plans."

So bankers might not want to feel too safe, even those seemingly vetted by the test. "The focus of the stress test was macro, not management," said Kip A. Weissman, a partner at Luse Gorman Pomerenk & Schick PC. Regulators' attitude might be "let's get to management later," he said.

In total, 10 of the 19 stress-tested banks were found wanting in common equity. Investors and bankers alike collectively exhaled because many had expected a worse outcome, though bankers have made clear that there will be more losses from delinquent loans.

Five regional banks - Regions Financial Corp. (RF), Fifth Third Bancorp (FITB), KeyCorp (KEY), SunTrust Banks Inc. (STI) and PNC Financial Services Group Inc. (PNC) - need to improve common equity. SunTrust, KeyCorp and PNC already have announced stock offerings.

The market for raising capital has improved; investors have factored in the potential dilution from capital raises and dismissed fears of nationalization, said Gerard Cassidy, an analyst with RBC Capital Markets. So government capital may well become more of an issue for smaller banks.

Cassidy said at least two chief executives at midsized regional banks are considered secure even if they need government support, because the banks already went through management changes: Huntington Bancshares Inc. (HBAN) and TCF Financial Corp. (TCB).

-By Matthias Rieker, Dow Jones Newswires; 201-938-5936; matthias.rieker@dowjones.com

(Henry J. Pulizzi and Michael Crittenden contributed to this story.)