在销售方面留下纪律是任何经理的挑战，特别是在倒下市场。但不是这样做的甚至可以赚到很好的经理。
在分析美国股票投资组合的总资产2000亿美元,波士顿咨询公司行为金融学卡伯特的研究发现,即使表现经理击败它们的基准可能失去超过100个基点的α-有时高达200个基点因为在什么时候卖什么东西的问题上做出了糟糕的决定。Cabot首席执行官迈克尔•埃沃里尼(Michael Ervolini)解释说:“经理买进股票可能有好的一面，甚至有高明的一面，但卖出股票要么(只是)不错，要么会影响业绩。”
事实上，Ervolini说，所有类型的投资组合的经理 - 小帽和大，价值和增长 - 可以学会做更好的销售工作。In a survey of 130 mostly U.S.-based professional investors, Cabot and the Charlottesville, Virginia–based CFA Institute found that more than 70 percent had an approach to selling that was not “highly disciplined [or] driven by research and objective criteria,” and that nearly 60 percent chose “observation” and “trial and error” as the basis for their sell decisions. “People spend their time thinking about buying,” Ervolini says. “There are a few rules or heuristics that are used for selling, but the vast majority of people do not have discipline or rigor in how they analyze sells.”
销售中可以造成的行为偏见是熟悉的行为金融研究的众所周知：销售获奖者太早锁定收益，持续到失败者太久，以避免承认损失，过度信任，风险厌恶，后视偏见。虽然一些经理可能倾向于一种特定的行为，但是其他管理人员可能在几个中替代，这取决于组合的表现方式。Ervolini, whose firm works with managers to identify and counter their behavioral biases, cites the case of one successful large-cap manager who became more risk-averse when the portfolio’s performance exceeded his benchmark and more risk-seeking when it was below — without realizing these shifts were occurring.
David Giroux，T. Rowe价格的联合经理大型价值策略，拥有150亿美元的资产，解释说他发现远离获奖者难以走出来。“通常你卖的是因为股票做得很好，但当事情上升并且情绪积极时，这是心理上难以走开，”Giroux说。“屏幕上是绿色的东西让你感觉良好，红色让你感觉不好。为什么你想卖掉让你感觉良好并且每天上升的东西？“
吉鲁指出，他此前持有的主要股票是制药商默克公司(Merck & Co.)。今年1月，该公司股价接近62美元，随后因与先灵葆雅公司(Schering-Plough Corp.)合作销售的抗胆固醇药物Vytorin的坏消息，股价下跌了三分之一。他怀疑自己等到股价超过51美元(他的基本面分析显示这是合理价值)之后再出手，是否冒了太大的风险。“这很难，”他说。“我们可能应该以52美元、53美元、54美元的价格出售，但我们等待了58美元、59美元，因为很难做出这些决定。”
In working with Cabot over the past two years, Mariko Gordon, portfolio manager of New York’s Daruma Asset Management, an institutional small-cap value manager with $1 billion in assets, found that her behavior is the opposite of Giroux’s: She tends to sell winners too quickly, and by dumping rapidly rising stocks well in advance of the portfolio’s average three-year holding period, she was giving up significant return. “We were one of Cabot’s guinea pigs,” she says. “We all know that we get in our own way as human beings, and we all have unique ways of getting in our own way.”
由于Daruma的投资组合有一个有限数量的控股（通常为30至35股），“我们不会让一个立场超过6％，我们将以5％的速度变得疲劳，”戈登说。“当股票做得很好时，我们的倾向于拿走桌子的倾向。”虽然有时，基金的任务需要这样的贸易（例如，当它搬出小帽领地或超过6％的投资组合时，必须销售库存，但是有时候，有时她已经屈服了卖得太快的习惯。基于对Daruma倾向的分析，Cabot每日分配每个公司的持有人“劝阻卖”或“青睐卖出”评级。
“我们已经增加了一系列额外的思想，”戈登说。“当我们审查投资组合时，我们现在被迫提出这个问题，这只是我们的瘙痒只是一种情绪反应吗？或者有理由出售相对于风险和基本估值？“