Identify the Cognitive Error Influencing Investment Decisions

Daniel is an experienced financial advisor who has built a solid reputation over the years. Recently, he started working with a new client, Sarah, who has a substantial investment portfolio. During their first meeting, Sarah expressed her concerns about investing in technology stocks, citing a major industry's downturn and several company bankruptcies over the past year. Despite Daniel's reasoning that current valuations are attractive and that he believes the sector will rebound, Sarah remains adamant about avoiding tech stocks. Daniel recalls that Sarah has a history of holding onto underperforming investments, often convinced they will recover. This behavior has led to significant underperformance in her past investment decisions.

In light of Daniel's observations regarding Sarah's investment behavior, assess which cognitive error is primarily influencing her decisions in this context?