A tale of two cucumbers

I don't really understand gardening. Guess that's kind of a given already! But my
cucumber plants are a case in point. A while back (can't remember when- October some time?) I planted some cucumber seeds. Two lovely seedlings duely appeared, and I carefully tended them. When they were getting to about 8cm tall I transferred them to the garden. So far, so good. And so same. But something has gone wrong.  I initially started this post when there were still two plants, although one was looking pretty bedraggled.  Unfortunately, one plant has now given up the ghost.  The other however, is going from strength to strength -

Early growth on my stronger cucumber plant

The poor weak cucumber plant which has now completely given up

The remaining cucumber plant going (and growing) strong

So what is the difference? Same soil same water same shade to start off - I am not too sure!  I'm starting to wish that I had some more seedlings ready to go- maybe it will just be one cucumber plant for me.  Can you get fruit from just one plant?  Much as I like the idea of growing from seed I think perhaps I am better with seedlings.

Mind you, my radishes are going ok, and they were just seeds sprinkled in the garden bed.

Early days of my radishes (and I think that was rocket seedlings coming up too - sadly the slugs seem to have destroyed them)

And radishes growing strongly - as my dad says (quite scornfully I must add) "even a child can grown radishes"

And here is my capsicum plant also grown from seed.

But this very prolific capsicum plant was planted from a seedling.

Lots of capsicums although they don't seem to get any bigger than this quite miniature size

So I like the idea of growing from seed, but for success I think seedlings are the way to go!