I'd like to see the whole plant if possible - are they in the ground or in pots? If they're in the ground, is your soil very heavy clay? How long have you had them? Are they in sun or shade, or partial shade? Have you inspected thoroughly to see if you can find the culprit?

how many leaves are affected? if it is just these then I wouldnt worry but of its many of them then I would suspect possibly vine weevil. did the leaves have reddish areas before the holes appeared if yes then that sounds like a fungal infection.

Hi. Thanks.. Then any suggestions how to treat vin weevil? Also how to treat fungal infection? .. Cheers

I';ve seen your added photos - they're in your gallery under Photos. Personally, I;d take a bet on slug/snail damage, but check for small green caterpillars too, though its a bit late in the year for them.

Just want to check - your plants are Photinia Red Robin and not Photinia Little Red Robin, are they?

Hi. Yes photonia res Robin. There small right now because they're only young yet. Thank-you.

I'd go with snail damage also. The tiny round holes towards the centre of the leaves is probably 'shot hole', which is a fungal disease and Photinia suffer from it anyway. Don't bother trying to treat it, as long as the plant remains healthy, it will tolerate it.