Easy, fast, and inexpensive
Shake flasks have been used for decades to cultivate bacteria and fungi, as well as plant and animal cells in suspension. Protocols have been established for all common organisms, even the more unusual ones. It is hard to imagine a biotechnology lab in industry or research that doesn't use shake flask cultures. They are an easy-to-use and inexpensive choice for basic applications, such as organism screening, media design, and early process development. All that is needed is a flask and a shaker to move it. The user doesn't need technical knowledge, advanced equipment or sensing and control technologies.
This very simplicity, however, is the biggest disadvantage. Shake flasks do not provide detailed insight into culture performance or the opportunity to monitor and control the process parameters.