All photo's that have been moderated and accepted are eligible for Photo of the Week (PotW), so long as they are uploaded by the due date for each week as follows:
The PotW weeks run from Saturday to Friday, and you need to upload by midnight the following Tuesday. So e.g. If Saturday was the 1st of the month, you would need to upload anything taken between the 1st and 7th (inclusive) by Tue 11th. NB the important thing is not the dates but the days.
If you wish to avoid your pics being in the PotW, the easiest way is to wait until the due date has passed and then upload.
The photo of the year is selected from those pics already awarded PotW.
It isn't a matter of scoring, and there are no hard and fast rules, except that the photographs must be taken within the qualifying week, and submitted by midnight on the Tuesday after the end of the qualifying week.
There is a rota of volunteer selectors, who look through all the eligible images, and whittle down to a shortlist of about 50. Individual selectors select according to whatever criteria they decide, and post the short list to the discussion forum.
They also notify the previous week's winner, whose privilege it is to pick the winner the next week.
The weekly winners eventually go forward to a selector who picks the image of the year from among the weekly winners.
Any member can volunteer to pick a week's selection. To volunteer, send a message to the Photo of the Year Co-ordinator.
The Photo of the Week competition is an informal competition intended to showcase some of the best images submitted during the week.
The only criterion for an image to be considered is that it must have been taken during the qualifying week, which runs from Saturday to Friday, and submitted by midnight on the following Tuesday.
Some people like to make sure that their images are submitted within the qualifying period, and other like to delay their submissions to make sure they are not considered.
What constitutes 'best' is very much subjective, because the selections of both shortlist and winner are done by different contributors each week.
As with all subjective selections, there is often disagreement with some of the selections, but that usually manifests itself by people saying which image they would have picked if it had been up to them to do so.
It all takes place in the Discussion Forum "Photograph of the Year (date)".