You're reversing the logic. Using your analysis, an entry is an individual who should get the first kills in a round. As such, whether or not the team converts the round or gets additional kills is irrelevant for his statistics, making them more relevant than for a player in any other position. Subsequently, a team depends on the entry to provide entries, and if they don't, then the team suffers. An example - Stewie plays like garbage for a month, Liquid's results are garbage.