As all investors know, the success or failure of shares comes down to investor sentiment in the short run. In that sense, as Benjamin Graham said, the market is a voting machine. However in the long run, he said that it’s more like a weighing machine where the quality of a company, rather than its popularity, really counts.

This situation appears to be highly relevant when it comes to Barclays (LSE: BARC). That’s because the bank continues to underperform most of its sector peers (as well as the wider index) even though its bottom line is still firmly in the black. In other words, it’s deeply unpopular among investors, with its share price fall of 25% since the turn of the year being evidence of this.

While such performance is disappointing, the unpopularity of Barclays could present an opportunity for long-term investors to buy at a discounted price. That’s because Barclays trades on a price-to-book value (P/B) ratio of only 0.6, which indicates that its shares could rise by 67% and still only trade at net asset value.

Certainly, asset impairments are a risk for any bank with the current outlook for the global economy being uncertain, but such a wide margin of safety indicates that there’s considerable upside potential for investors in Barclays.

That’s only in the long run though, when Barclays’ growing profitability and improving efficiencies are likely to gradually change investor sentiment in the stock. In the meantime, Barclays seems to be suffering from a mixture of internal uncertainty, external uncertainty and a general apathy towards the banking sector.

Uncertainty persists

Internally, the bank still seems unsure of its long-term strategy. That’s at least partly because it has only recently changed its CEO and it seems likely that he will formulate his own direction in which the bank should move. While this seems likely to involve taking more risk via investment banking, the market remains unsure on the actual future direction Barclays will take, although more should be known on this subject following the bank’s update next week.

Externally, Barclays continues to have the threat of fines hanging over its head. This situation could last a while longer and seems to be a reason for investor sentiment in the company being very weak. Meanwhile, investors appear to be somewhat nervous regarding the outlook for the global banking sector owing to the potential for an economic slowdown due to a more hawkish Federal Reserve and a slowing Chinese economy.

As a result of these factors, Barclays is undeniably an unpopular stock at the moment. In the short run, things could get worse before they get better and Barclays’ share price may suffer from the stock market being a voting machine where investor views matter. However, with such a low valuation and the prospect of a new strategy alongside rising profitability, Barclays seems to be all set to deliver long-term share price growth as the market turns from being a voting machine into a weighing machine.

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Peter Stephens owns shares of Barclays. The Motley Fool UK has recommended Barclays. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.