Overwatch - Solo Queue Problems

Inaccurate image: Speaking from experience, healers switch out when they're tired of two snipers and three useless-but-kind-of-annoying flankers not grouping up and protecting them. Having such a well-rounded team like the one above is rare.

For me it doesn't have to be so drastic. If I'm a healer and I feel like I'm unable to contribute cause I'm dying too fast or whatever, I'll switch out. If I'm not able to heal my team in the first place what difference does it make?