The problem with the above statement is that the word 'want' can be construed very differently.
I wrote a semi-successful novel. Some people liked it and some people hated it. I don't think it sold very well, but these days that's apparently not unusual. I didn't write it in order to write a successful novel (though of course did all I could to make it so) but because it was like some incredible burden I had to take and deposit in a certain place before I could get on with my life. Now that all three novels have been published for some years (it's three since my third and last novel, The Offering, was published), I can see that I have learnt some things.
1) Success is never un-qualified, with it usually comes criticism and unless you have very thick skin this can be endlessly disturbing; i.e. you go on being disturbed by it, like you would by a pain in your side or your back or your foot, for perhaps the rest of your life.
2) Funnily enough, the very fact that you have written a book will render you unable to defend it or to explain it because to do so would be in bad taste.
3) Your work may be praised by people who love other novels that you don't, in which case, the praise does not mean a lot.
4) Your work will possibly be both praised and vilified, in a contradictory way, to a laughable extent, until one day, after months of feeling devastated, then elated, then devastated, then elated, you wake up feeling simply empty, finally realising that none of it means anything at all. (Except that you don't; the criticism will far outweigh the praise in your mind)
5). The book will not change your life, except possibly financially. Your life, be it easy or difficult, will still essentially be the same afterwards. In fact 'fame' and success can magnify inner pains and insecurities, which, in contrast to their starriness, suddenly appear in sharp relief.
6) The book will fade astonishingly quickly and while you
are still drawing breath after finishing the marathon that nearly killed you, will be asked what you are working on next.
So if you have written the 'successful' novel for the sake of writing a successful novel, there may well be some hidden aspects of the outcome you did not suspect. The successful novel may also prove to be a curse; a mill stone around your neck. If, however, you wrote not to write a successful novel, but simply because you wanted to, it will have been worthwhile, whatever the outcome.
How to Write a Successful Novel