[roeme]

Usually, there are practically no downsides to it, unless there is a fundamental problem in your $ORG.

1. First of all, it will get you connected to the users which depend on your $APP/$SYS. Hard. You will get to know their struggle/woes - it's not just some ticket you can work on at your leisure.

2. If it's your stuff that causes problems, you will get your shit together and make sure that it works, code defensively, and test thoroughly - whatever necessary. After all, you don't want to deprive yourself unnecessarily of sleep – or others, after the experience.

3. If it's not your stuff that causes problems, you'll get the oppurtunity to “yell” at the people responsible for it. And they must act on it - nobody cares on the why or what, if people have to get up in the middle of the night, it costs the company¹, and everybody gets upset.

It only impacts your health if you get called up regularly, and no actions are taken to remove the root causes of it. Or you can't take any.

It's less of a technical problem, but more an organizational one, so – as it already has been said in here – you should talk to the people of the team, not HN.

¹) If it doesn't cost them, be wary.

[gaius]

The downside is it's usually cheaper and easier to call you than actually fix root causes. Then it's not on call, it's beck and call. Even if you are paid double-time for it, the company figures that's a sunk cost so just call him anytime, for anything.

[arthurjj]

I can second this. If you can't fix the underlying reason that you were paged at 3AM it gets old fast

[serge2k]

Downsides are that you become a slave to the pager. Everything you do for that week revolves around having to potentially take a page anytime.