Stocks continued their summer rally on Tuesday, with several major benchmarks setting or flirting with new highs. Many commentators have noted that the current bull market in stocks, which has lasted since the end of the financial crisis, will soon be longer than any other market advance in history. That's good news for those who think the momentum can continue, but some nervous investors fear that gains are getting overextended. Regardless of the overall direction in stocks, some didn't participate in today's rally. TD Ameritrade (NASDAQ:AMTD), J.Jill (NYSE:JILL), and J.M. Smucker (NYSE:SJM) were among the worst performers on the day. Here's why they did so poorly.

TD Ameritrade deals with competitive threats

Shares of TD Ameritrade fell 7% on a poor day for brokerage companies overall. Wall Street giant JPMorgan Chase sent shockwaves across the industry when it announced that it would offer a new service that lets clients trade stocks at no commission, further extending a trend toward lower fees that has been going on for several years. Competition among brokers has been fierce, and with the potential loss of commission income as a revenue source, TD Ameritrade will have to work even harder to make sure its value-added services remain popular enough to produce the level of profit that shareholders want. Otherwise, today's decline could be the beginning of a longer downturn for TD Ameritrade and many of its brokerage peers.

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Image source: Getty Images.

J.Jill leaves shareholders wanting more

J.Jill stock dropped over 10% after the women's apparel retailer announced its second-quarter financial results. The company said that both revenue and earnings were down slightly from year-ago levels, and even though comparable-store sales managed to edge higher by 2.2%, J.Jill doesn't expect that good result to last. Projections for the third quarter include a decline of between 2% and 4% in comps, which came as a shock to many of those following the stock, as they had expected an increase of as much as 4% year over year. Despite positive comments from management, shareholders are nervous that J.Jill isn't setting itself up to go into the key holiday shopping season with positive momentum.

Smucker can't sweeten up its investors

Finally, shares of J.M. Smucker declined nearly 7%. The maker of peanut butter, jam, and other consumer and pet food items reported a 9% rise in revenue in its fiscal first-quarter results, helping to send adjusted earnings higher from year-ago levels by 18%. Yet investors had hoped for a stronger performance from the jelly maker, and Smucker also reduced its full-year guidance for sales and free cash flow. As investors saw last quarter, Smucker has had to deal with increasingly popular food entrepreneurs at the same time that it struggles to maintain its competitive advantages in working through traditional grocery store retail outlets. The company has plenty of plans to remedy the situation, but it'll take more time than shareholders want for Smucker to get everything figured out.

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