Since stunning the markets with unprecedented monetary easing in April, the Bank of Japan has taken a back seat, failing to offer solace to investors that have been rattled by violent swings in the country's bond and equity markets.
According to Kathy Lien, managing director, BK Asset Management, the central bank's "overconfidence" is to blame for the instability plaguing the market.
"They did nothing because they were stubborn and overconfident that their policies were enough to stabilize markets and the markets said no," Lien told CNBC Asia's "Squawk Box" on Friday.
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"This is Japan's own doing, they had the opportunity to provide markets with a small dose of stimulus in the form of increasing asset purchases or even the maturity on fund supply operations and they did nothing," she added.