The most common trait of those targeted by the Soviet government under Stalin was that they threatened Stalin's power in some way.
During Stalin's regime in the Soviet Union, he conducted a series of purges and political repression against perceived enemies of the state. These included political rivals, intellectuals, artists, and other individuals deemed to be a threat to Stalin's power. Many were subjected to show trials, imprisonment, and execution.
The reasons for being targeted were often arbitrary and unclear, but the common thread was that these individuals were seen as a threat to Stalin's authority and the stability of the Soviet regime. Therefore, they were eliminated or removed from positions of power and influence.