system
Given the following post, respond as if you're commenting on Reddit:
human
CMV: In games with repeatable daily content, the content should always reset at a set time and not 24 hours from the previous attempt.

I've run into this in several games over the years when you are allowed to buy X item from a shop once a day, or you are allowed to fight X monster once a day. 

To enforce the "once a day" part, game developers have two choices. They can either have the game reset at a certain time of the day (say midnight, GMT), or they can use a timer and have the game reset at 24 hours after the last attempt. My view is that with very few exceptions, the game should always reset at a set time.

The timer method is inconvenient, and causes you to miss out on potential gameplay. For example, say on the first day I first kill the monster at 7:00 before I go to school. On the second day, at best I am going to be allowed to repeat the action at 7:00 plus whatever time it took me to complete the activity, so like 7:05. Realistically, I'm probably not going to start at the exact second that the timer expires, so say 7:10. On the third day, this compounds, and I'm starting at 7:15, then 7:22. Eventually, I can't do it before school so I have to wait till I get home and start the timer at 3:00, then 3:10, etc.  If I have anything going on in my life that doesn't allow me to be near the computer at those times, I could lose multiple hours. Soon, I've lost a day. 

Contrast this to the "reset at midnight" method. The timer resets when I'm sleeping, and I have the entire day to complete the activity. I'll never lose out on gameplay as long as I can play at least one time during the day, at any time that I chose.

I can only think of two exceptions to this. First, if the game developer determines that resetting at a specific time will be gamebreaking due to technological limitations. I could see that having a huge rush of people doing X activity at the same time could conceivably stress the game servers and crash the game. 

Second, if there is legitimize concern that resetting at specific time will harm gameplay in some way. Maybe having a rush of items entering the game economy all at once would be detrimental. However using "gameplay" as an excuse should be seriously weighed against the inconvenience that it would cause. 

I can think of several other reasons that a timer would be used, but none of them outweigh the inconvenience to the player. In order to change my view, you will need to both present a reason to have a timer, and also make a case that the reason is important enough to override the downside of having one.
gpt
I have seen this practice take place a lot in mobile games and at least in those games it seems to be more of a way to get players into a schedule that keeps them playing the game. Often features of game design that might seem annoying to some are really in place to hook others, i.e. loot boxes or pay to win elements. By having an action that you can only repeat every 24 hours from a set time, that action might become part of your daily routine. For example if you play a farming game on your phone harvesting your crops every morning at 8am can easily become a daily habit. If the clock resets daily however, players have a lot more freedom to do the task whenever they want, increasing the chance that it falls out of their daily routine. Having players repeat the same task everyday at a specific time is what a lot of these devs want, as it keeps you in the game. Overall the potential profit that repeatable actions bring is most likely greater than the inconvenience to players.