Electoral rules and party candidate selection processes both affect legislators' behavior, specifically, their tendency to either toe or break their party's line. However, elections and selections may produce contradictory incentives for legislators, leading us to ask how conflicting motivations affect legislators' tendencies to dissent. I argue that the effect of these two institutions is conditional and that legislators who face contradictory incentives will tend to maintain voting discipline. On the other hand, when the incentives of elections and selections align, they tend to amplify one another. This is especially true when elections and selections both incentivize personalization. In this article, I test and find support for the conditional hypothesis using an original individual-level dataset with more than 6,700 legislators from thirty country-sessions.