It is an unfortunate reality of technology development that emotional factors bear on the commercial potential of an invention. Because invention development requires capital and investors are people who are susceptible to fads and are driven primarily by greed and fear, the commercial potential of an invention at one point in time can be different from that at another. For this reason, it is important to assess whether the invention is in a field that has "sizzle." For example, Internet-based technologies were on investors' hot lists during the mid 1990s.