Snooker

Spotting perfectly is basically impossible unless you can take the time to get down and use parallax alignment and baulk line reflections to see that everything is in the correct place.

Even with that, which one can only do at the beginning of a session, the two axes that are impossible to check are the height of the black spot down the table and, incredibly, the centre line on which the brown, blue, pink and black sit.

In practice, the latter is usually OK because one spots the brown and black by pulling them towards the cushion directly toward the spot. These can then be used to align the blue and pink.

So, we are left with the black being only best efforts in terms of low or high.

Now, consider that the tables are setup in advance of the audience arriving, the MC giving their practice chat, the actual introductions, the walk ons, the handshake, the cue chalking, the applause etc etc.

This results in the balls sitting on the cloth for much longer than one would like, before the match begins. And it may then be a while before the colour is disturbed.

All on top of the finest possible clothes on tables heaterd to 40 degrees C.

This all goes to say that the incorrect position divot of the black may be beginning to form before the first time the black is moved.

From there, a fast player in and around the black spot, on a century break? Yep, that ref will be spotting quickly and causing a positive reinforcement loop on that divot.

Boom. Damage done, but no bother at all, until precisely the situation we saw with RoS and Desislava occurs.

Hope that helps illuminate it a bit.