You know, it's funny you should say that -
'Thankfully I have a way of forgetting the hardship immediately after it's finished! '
I am exactly the same. Obviously for the purposes of writing I must remember the details but whatever feelings of frustration or excessive challenge there were leave me as soon as I deliver and see the joy and satisfaction on my clients' face. I really enjoy the 'reveal' as it were :D
Whilst the payment is undoubtedly essential, the joy of getting it right far outweighs the joy of payment, and retrospectively I only remember the good bits.
Have a great day