If you’re playing against a lot of players, especially those who are proficient with the weapons, it can be incredibly frustrating to actually infect anyone, due to weapons like the Double Barrel killing you before you can even get close and Sonic Shotguns blasting you backwards.
It often seems like it takes order of magnitudes more skill to be a threat to the survivors than it is for the survivors to be a threat to the infected. To combat this, it could help to have multiple people become infected when the round starts, so the infected start off being able to make more advanced plays like distracting the survivors, rather than just having to run at survivors until one of them happens to miss enough shots.
Enraged mode honestly doesn’t help that much, at least for me. Even if it did, it’d only show how powerful the weapons are if the infected need a temporary buff just to survive.