When investors are left holding a pile of trash, it means that their investments have failed to generate a return. This can happen for a variety of reasons, such as a company going bankrupt, the stock market crashing, or a particular sector of the economy performing poorly. In these cases, investors may have been speculating on the potential of the investment, but unfortunately, their speculation did not pay off. In some cases, investors may be able to recoup some of their losses through litigation or other means, but in many cases, they are simply left with a pile of trash.