Why do we need daylight saving time?

I always wondered — what’s the real need for Daylight Saving Time (DST)?
As a kid, our school simply changed timings for summer and winter months — and we all followed it without any confusion!
Why not do the same at a broader level — adjust office or school hours locally, instead of forcing millions of people to change their clocks?
Yes, with digital watches and smartphones, updating time is less painful — but the ripple effects are still very real.

Think about remote teams or offshore folks — suddenly, their working hours change, since DST has kicked in!

Historically, DST was popularized during WW1 to save fuel (less artificial lighting = less coal burning).
But here’s what’s funny:
Modern studies show DST barely saves energy today — just 0.5% to 1% reduction in electricity usage in some regions.
Meanwhile, workplace productivity drops for a few days after the shift, thanks to sleep-deprived, confused folks reaching the office.
Heart attack rates even spike the day after DST kicks in! (Source: American College of Cardiology)

What’s your take on the DST story?