I took the effort to search this and the "count to 2000" topic for mistakes.
Basically, the value of the number must decrease by 1 with each post. I found 2 types of errors on my search: Repetitions and increments.
Repetition means that someone did not reduce the number of the previous poster, but simply copied it. He copied it even though the number was meant to sink. This causes a mistake to occur which increases the final total by 1.
Increments occur when the poster does not decrease the previous number, but increases it. This increases the value of the total number by 2.
From time to time I came across something more complicated. Sometimes a poster counted up, increasing the number by 2.
The next one then tried to correct this value and counted down 2.
But this corrector overlooked that his post is also meant to count down. So to do it right, he would have to count down by 3.
With this, I would like to illustrate it:

In the following, I'm going to mention the number of the reply which did the mistake and the type of the mistake. Behind it I then describe how the final number was affected.
Reply #34, incremented, partly corrected, +1
Reply #49, incremented, +2
Reply #69, incremented, +2
Reply #415, incremented, partly corrected, +1
Reply #1710, repeated +1
Reply #2244, incremented, partly corrected, +1
Reply #2374, incremented, partly corrected, +1
Reply #2474, repeated, +1
Reply #2774, repeated, +1
Reply #2866, repeated, +1
Reply #2927, repeated, +1
Reply #3098, repeated, +1
Reply #3342, incremented, +2
Reply #4003, repeated, +1
Thus, we are 17 numbers above the actual value.
Now my question is, how do we move on?
If we continue without change, then my number is 3,565. If we would see my post as a correction, then my number would be 3,548.
Another way to find the correct number is to subtract the start number 10000 from the reply number. My reply would have the number 6422, so 10000-6422 = 3578.
With this trial I come to another number. Although I documented the mistakes with screenshots... So I'm hopeless.

What do you think, what should we do?