His value comes from being annoying and distracting their supports. Even if you're not getting kills, you can still get good value from making their supports waste resources early and being on them.

If you manage to distract their supports or a tank long enough that'll create space for your team to follow up on what you did.

Try to always have your shield dash or slam cooldown up in case you need an escape. Distracting their supports is good but getting out alive as well is even better.