Well begun is half done

I don’t know how right or wrong this is for the first post on my blog. Will I end up proving a point or will I just prove this particular proverb true? I have no clue. But it is something that has always made me wonder and I really do need some answers.

There are innumerable proverbs in the English language; some bang on target, some totally outdated, some weird, some funny but the one which has always irked me to no end is –‘well begun is half done’. Why? Whatever could be the reason for someone to coin this phrase? Should you not begin something well? Does it mean that in order to complete any job you have to mess it up in the beginning? Begin well and complete a job properly. Is that so hard to do?

Agreed that initial over enthusiasm can lead to a slump going forward. But well begun can be well completed. It is all about liking what you do. If you like something you will obviously begin the job well and see to it that it is completed in time and in the manner required. And if you do not like something any beginning will not lead to a successful or happy ending. A job disliked is never done –half or in full.
Can I humbly suggest a rephrase –like begin like done.