A trader or investor who makes poor trades and ends up with heavy losses over time would be considered a lame duck. Often, if a trader goes bankrupt, it is not the result of one bad trade but a long string of them - such a trader is called a lame duck because he or her is ineffective as a trader. (The term lame duck also refers to a politician who has chosen not to seek re-election, is ineligible to run for office again or has lost an election but is still in office until the election winner takes control of the office. The politician is considered a lame duck as he or she is not accountable to the constituency he or she represents.)
Investment dictionary. Academic. 2012.