Why does uploading pictures or indeed any files seem to be so slow and difficult

[#1]

I have seen this a few times now whilst replying to post  with no pictures, either through the quick reply or main reply options, however the post goes through and a simple press on F5 to refresh the page clears it
Edit:
Whilst posting this I had the usual green spinning circle in the tab, and opened a new tab seen it had indeed posted refreshed the original tab and all was ok again

[#2]

Another failure while making this post: http://community.plus.net/forum/index.php/topic,122573.msg1062972.html#msg1062972
Still spinning but looking in another tab it was there.