You work with big data, need real-time database connections, or lack an official portable license.
You frequently analyze data on restricted public computers and can accept slower startup and processing times in exchange for full SPSS functionality anywhere. Ibm Spss Portable
However, for most users, the standard installed version or SPSS Cloud subscription is more reliable. If you decide to go portable, invest in a high-speed USB 3.1 drive and understand the licensing limits. You work with big data, need real-time database