The colour says that something moved. Only you know why, so the card keeps a place for it, on the day it happened.
The example month as the time view would draw it, simplified: the line is the daily total, the orange lines the 7- and 30-day normal, the grey band the campaign, the dashed grey line the low trigger, the dark step the target, and the ocean dot the comment on day 22 - the same symbol as in the Dashbox mark. The marks along the bottom are the events.
A comment belongs to a date: "the sign-up form broke after the release". On the time view it is a mark on its day; an important one gets a dashed line and a short callout. A comment on a collector shows on all its cards, so "the source was down 3-5 October" is written once.
A period covers days or weeks: a campaign, a release window, a price change, a holiday. It is a band behind the line, and it can still be running.
Next month, looking back at a dip, the reason is on the same line as the number, next to the events and the target. That is the half a dashboard does not keep.
Dashbox does not write these for you and does not guess a reason. It compares, colours on a real move, and keeps what you add.
In the example month
An example, not real data.
Day 12
A newsletter campaign starts. You add a period, "Newsletter", with no end date yet.
Day 19
The campaign ends, and you end the period. It stays on the time line as a band from day 12 to day 19.
Day 21
Rose after the campaign, and the band beside it says why.
Day 22
You add an important comment: "Sign-up form broken after the release".
Next month
You open the time view to see what happened to sign-ups. The line, the campaign band, the comment on day 22, the event marks and the target stepping from 30 to 35 are in one picture, and the history under it lists the same in order. The dip has its reason, written on the day it happened.