It can be tricky to ascertain which investments are worth making -- THIS IS WHAT SENIOR ENGINEERS ARE FOR -- but good investments pay off a thousandfold or more.
And advertise the hell out of your successes, so that you earn more currency/credibility for next time.
If you did a hard rewrite that's still paying dividends months or years later? KEEP TALKING ABOUT IT. Keep rewarding the people who pushed it through against all odds. Praise the actions you want to see more of.
Your job as a manager is to lean hard against tendency. MAKE it visible. Point it out, celebrate it, repeat til long after you're sick of saying it.
This builds trust in your team, too. People need to see an accounting for the currency they give you.
You need to exercise both. And reward them right up there with feature work.
Without them you will grind to a halt for opaque and frustrating reasons at the worst time. Without them you will slow down and drive good people to quit.
On call is not a panacea for all dysfunction. It's just a really powerful tool, to be creatively deployed as part of a full suite of solutions.
But I'm not crazy. It's a lot of work to get there. No shame to those who are starting many steps back.