Lots of comments here about sundials and the equation of time, responding to OP comment that sundials suck.
The actual issue is that sundials reflect the movement of the sun, whereas we mainly use an averaged out mean time to describe when it is noon. Solar noon (when the sun is at it's highest point) is sometimes ahead of mean time noon, sometimes behind it. This is due to the movement of the earth around the sun (including whether the earth is east or west of the sun looking down from the above the sun), the earth's axial tilt, and your latitude. However, the variation is entirely predictable, as encapsulated in the so-called equation of time, which shows the variation that needs to be applied to get mean noon. Of course, none of this really matters if you aren't bothered about synchronising geographically distributed clocks, time zones, etc.
As an example of the other weirdnesses that can result from using solar time, consider how day length changes as we go from the shortest to the longest day. Where I am in the southern UK, sunrise continues to get later until about two weeks after the shortest day, and the major change of day length (at that time of year) is in the evening. This is the same effect captured by the equation of time and reflects the fact that we are on a wobbly planet that doesn't have a perfectly circular, perfectly vertical orbit around the sun.
Comments
Lots of comments here about sundials and the equation of time, responding to OP comment that sundials suck.
The actual issue is that sundials reflect the movement of the sun, whereas we mainly use an averaged out mean time to describe when it is noon. Solar noon (when the sun is at it's highest point) is sometimes ahead of mean time noon, sometimes behind it. This is due to the movement of the earth around the sun (including whether the earth is east or west of the sun looking down from the above the sun), the earth's axial tilt, and your latitude. However, the variation is entirely predictable, as encapsulated in the so-called equation of time, which shows the variation that needs to be applied to get mean noon. Of course, none of this really matters if you aren't bothered about synchronising geographically distributed clocks, time zones, etc.
As an example of the other weirdnesses that can result from using solar time, consider how day length changes as we go from the shortest to the longest day. Where I am in the southern UK, sunrise continues to get later until about two weeks after the shortest day, and the major change of day length (at that time of year) is in the evening. This is the same effect captured by the equation of time and reflects the fact that we are on a wobbly planet that doesn't have a perfectly circular, perfectly vertical orbit around the sun.
[Edit - minor rewording for clarity]
Thanks. Thats new information to me that sunrise and sunset don’t move uniformly.