we tend to like solutions that will resolve problems over long periods.
A cheap clone will have a resonator. the errors will be in multiple minutes per day
some Arduinos will have crystals and the errors will be greatly reduced.
all microcontrollers without an RTC will add or subtract seconds or minutes per day.
An RTC can be had for a few dollars and be added to almost any microcontroller.
a micro-controller that has Wifi and can access the internet, can pull time from the internet.
I imagine that if you have a home WiFi, that there might be some way to pull time from you cell phone or computer or any other device on the WiFi, probably more trouble than needed.
if you are fine with your device adding a couple minutes per day, then there is no need.
if you are doing something like watering plants, you can use a sensor to sense sunrise and just set your water schedule to be an hour after sunrise, 45 minutes before, an hour after sunset, 53 minutes before... etc.
Since the sun rise and setting times change daily, you can write some code to follow the change and even allow to cloudy days.
The answer is how concerned are you that if, after a month, the start time if off by an hour ?