The advantage of daylight savings is I can set my schedule to wake up at the same time each day, while maximizing my daylight hours and never getting up before dawn.

Without the shift for daylight savings, the sunrise time in San Francisco varies from 5:47a at the summer solstice, to 8:25a just after winter solstice. If I set my schedule to get up at 8:25a every day, I'd miss a significant amount of morning sunlight.

The beauty of daylight savings is it shifts the sunrise time to be earlier in winter, so instead of 8:25a the sun rises at 7:25a. Thus I can set my schedule to get up at 7:25a and get an extra hour of sunlight every day.

(Technically the latest sunrise time is just before shifting from daylight to standard, 7:39a on November 5 - the point is we reduce the range of variation from 2hrs 38min to 1hr 38min)