It’s not terribly often that a player fails to make the team, yet gets invited back to training camp the following season. Or accurately, I should say that the majority of said players do not get that opportunity, as there are usually at least a few practice squad players from training camp that get signed to Reserve/Future contracts the following season.
This summer, the Pittsburgh Steelers return six first- or second-year players who spent training camp with the team last year but failed to make the 53-man roster in any capacity, including two 2014 NFL Draft selections.