It was there when I pressed the shutter release ......

The most useful photographic advice I ever received was "if you want people to believe you're a competent photographer, never show anyone your failures". That's meant dumping well over 99% of my photographs, which is much easier and cheaper to do in these days of digital photography, when they disappear into the ether with the click of a button, at no cost. 

But digital photography also delivers its own special kind of failures, thanks to the phenomenon of shutter-lag - that interval between pressing the shutter release and the sensor capturing the image. So I've got plenty of pictures like those below, which looked really good when I composed them and pressed the shutter....

This long-tailed tit was sitting perfectly on that twig in the foreground, looking at me over its shoulder as I pressed the shutter release  ..... it must have taken off like a rocket.

In those last few milliseconds, this pigeon decided that it didn't want any publicity. Its feet came out well, though ...

.... and this guillemot was overcome with shyness at the last moment too....