1. A method comprising: executing, by one or more computer processors, a software program, the software program requiring one or more physical interactions with a user through an input/output (I/O) device, wherein each of the one or more physical interactions includes respective predefined dimensions indicating a proficiency in performing one of the one or more physical interactions, and wherein the one or more physical interactions include: user input interactions, help usage interactions, error recovery interactions, task completion interactions, and tutorial completion interactions, and wherein the predefined dimensions for the user input interactions include: a typing speed, a typing accuracy, and a number of typing shortcuts performed; tracking, by the one or more computer processors, the one or more physical interactions; generating, by the one or more computer processors, a familiarity profile for each of the one or more physical interactions based on the respective predefined dimensions for each of the one or more physical interactions; customizing, by the one or more computer processors, the software program based on the familiarity profile for each of the one or more physical interactions; executing, by the one or more computer processors, a second software program, the second software program requiring one or more physical interactions with the user through the I/O device; determining, by the one or more computer processors, whether the second software program is related to the first software program; and responsive to determining that the second software program is related to the software program, customizing, by the one or more computer processors, the second software program based on the familiarity profile for each of the one or more physical interactions for the software program.