I entered mock data just to see what happens, and the goal instantly derailed and recommitted, without ever going red or waiting for the the time to be up.
This isn’t necessarily bad, but seems inconsistent with the way goals generally behave. Is it because it’s clocky? Is it because max pledge is zero?
Some important information is missing here! What was the type of goal, rate, and mock data you entered?
Aren’t you able to see it from the link?
No
Thank you for posting about this bug! In order to understand your report, though, we would need a little more information from you.
If you’re willing to help Beeminder out, it would be very helpful if you could explain a little more about exactly what happened. A link to a graph doesn’t explain anything, and that picture doesn’t tell us the relevant information.
Thanks for mentioning this was weird for you! Always interesting to hear what’s surprising for folks. The reason a goal will typically recommit immediately is when you change your data in a way that puts you on the wrong side of the road for yesterday. This might involve adding data for a do-less goal, or removing data on a do-more goal; because the graphs are almost all cumulative, it can happen even if you enter or remove data from weeks ago, because that still drops the whole line of your data down from that point, or pushes it up since that point.
So the current criteria for derailment is “in the red yesterday”. It used to be “two red days in a row”, but this actually created a loophole and was just not a great idea.
Ah. I see. I must have reported it on yesterday’s, not today’s, date. Tried to report one on today’s date and it worked as expected. Thank you for the explanation.
Don’t worry about just posting a link to the graph or a picture as part of the explanation, @ioioio. That’s totally fine in this forum category. Other users don’t have access to your data or history (which is why @zedmango couldn’t pitch in without more info) but the workerbees here can dig into the history to uncover things.
Never feel dissuaded from reporting a bug over thinking you might not give enough info! Having an early warning that something’s up (or confusing) is way better for us than having perfect knowledge of what happened!
It’s all good! You were wanting to help out and needed more info if you were going to do that. (And we post stuff about the shape of bug reports and all that and that could come across as requirements. It’s more like chatting and musing about the platonic ideal vs requirements. The best bug reports are the reported bug reports.) 
Thanks for being keen to help out a fellow beeminderer.
