"Economic success is fleeting," and booms tend to spur countries into heavier debt loads and a sense of political complacency, especially if political leadership has gone "stale," he said. As an example, he cited India, which after a decade-long boom, shifted into a period of policy paralysis, leading to high inflation and low growth.
"Countries only tend to carry out economic reforms when they have their back to the wall," he said. "Once they carry out some economic reforms, you end up getting an economic revival," Sharma said, adding that a leadership change also helps to spur strong equity gains.
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Over the last 20 or so years in emerging markets, "equity markets tend to outperform massively in the next 12-18 months after a new leader comes to power," he said.
"If you look at the best performing markets in the world this year, they've really been markets where they've been anticipating political change and there are reform minded leaders coming to power," Sharma said, noting Asia's two best performers this year have been India and Indonesia, largely on expectations for political change.
But while those two countries still meet his criteria for gains ahead, sentiment on the markets is already optimistic, and the best risk-reward is likely found in emerging markets in Eastern Europe, he said.
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"Sentiment is still so beaten down and yet the balance sheets are in much better shape and the economic recovery is taking place," he said, adding he's positive on Poland, Romania, Greece and the Czech Republic.
But he's keeping an underweight call on Russia.
"When governments are in power for more than 10 years, that's very counterproductive for economic reform and for economic growth," Sharma said.
Others also see a pattern in seeking out the emerging markets' underachievers.