[cc]

A sort of blossom end rot.
The tips of most are brown and rotten.
Some are making it. Can't remember which one it is but it produces fat yellow ones. Growing in a large pot. Definitely keeping up with the watering. Not that that's particularly hard at the moment. Any way pictures included. Rotting while still small.
Thanks in advance. cc

[Subversive_plot]

It's exactly that - blossom end rot (BER).  With courgettes, it is often associated with the female blossoms not getting pollinated.

Try pollinating by hand. I use a small artist's paint brush to gather pollen from male blossoms (long thin stem, internal structure a single fuzzy column covered with pollen; pollen can also be gathered where it drops from the column into the flower).

Transfer the pollen with the brush onto the reproductive part of female flowers. Female flowers have a shorter stem, shaped like a miniature fruit. The interior reproductive structure is complex, looks sort of brain-like.  That structure is where you wan to deposit the pollen.

I did this all summer and have produced many courgettes. It is best done in the morning while the flowers are open and fresh, each flower is open for only a part of the day, usually morning.

Good luck!

[mumofstig]

It's because the flowers didn't get pollinated 
If you've got the patience you can hand pollinate the flowers - just take off a male flower, tear off the petals to expose the stamens and make like a bee inside the female flower. 
One male flower (the ones without a baby courgette behind) can pollinate 2 or 3 female ones.

Sort of snap, SP 

[missmoneypenny]

I read somewhere that if mud gets splashed in tube flower while you water, this is what happens. I guess again it’s because it doesn’t get pollinated.

[cc]

Thanks all . I am having a problem find a male one.
I may have a lesbian courgette plant!!

[Kleftiwallah]

I have another courgette question. 
Why do some grow evenly all along their length, but others swell up from the plant end?

Cheers,  Tony.

[Subversive_plot]

I have another courgette question. 
Why do some grow evenly all along their length, but others swell up from the plant end?

Cheers,  Tony.

I have had that happen.  My guess is a low rate of pollination (I decided to check that guess, and found this [url]https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjvqZKbjMaAAxW1I0QIHRSUAUIQFnoECBEQAw&url=https%3A%2F%2Fwww.gardeningknowhow.com%2Fedible%2Fvegetables%2Fsquash%2Fpointy-squash-bottom.htm&usg=AOvVaw2okQLEhOwAxjrMJZo8zL2p&opi=89978449]https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjvqZKbjMaAAxW1I0QIHRSUAUIQFnoECBEQAw&url=https%3A%2F%2Fwww.gardeningknowhow.com%2Fedible%2Fvegetables%2Fsquash%2Fpointy-squash-bottom.htm&usg=AOvVaw2okQLEhOwAxjrMJZo8zL2p&opi=89978449][url]https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjvqZKbjMaAAxW1I0QIHRSUAUIQFnoECBEQAw&url=https%3A%2F%2Fwww.gardeningknowhow.com%2Fedible%2Fvegetables%2Fsquash%2Fpointy-squash-bottom.htm&usg=AOvVaw2okQLEhOwAxjrMJZo8zL2p&opi=89978449 )

[mumofstig]

I think that it works like this....some modern hybrids are self fertilising, so seed set is even along the fruit, the ones that grow bulbous at the end, are older varieties and only the seeds at the 'fat' end have been pollinated.
I think that's another snap SP 

[Kleftiwallah]

Thank you very much Subversive_plot,

 that was interesting reading, I've never heard the phrase
bottle necking before, it suits the problem exactly. 
But far too many references to "disposal of the fruit"!

Cheers,  Tony.

[Subversive_plot]

Well... if they do go bad, I'd dispose of them.  If the fruit is just weird-looking but otherwise good, I eat them!