Continuing from DeadSerious's post... It all depends on what kind of site you own. If you own a site that is information based then fast loading usability is key. Because while i am surfing your website trying to find out what the first domain ever registered or what time the 59 or 61 busses stop at the end of my street (:00 and :05) then i want to be able to find it (Usability) and find it fast (Usability + Fast Loading) But i shouldn't really say its just information based websites, because every website should be usable and fast loading. Its just that some sites can get away with adding a little time to the load depending on what it is its based on. An Entertainment website with alot of information on one page, perhaps an index of all the web cartoons that they have, should be allowed to add a little more to the site even if it means load time goes up another second or two.
I guess it all really depends on how much time your visitor is going to spend on the website thats loading. I would hate to wait 10 seconds for a page to load that i'm only going to be at for 5 seconds, or even another 10 seconds ontop of the loading.
Even though Load Time is important its often the last thing on my mind when i first start making a site. Heres the steps i take when designing
-Get an idea of what will be on the site and the name of the site.
-I Think about the general design of it and draw it out in Photoshop or another graphics program.
-When i'm finished the design i cut it up into smaller pieces and piece them together in Frontpage (I really shouldn't use frontpage for this)
-I then think about ways to cut down on Load time by eliminating certain parts of the graphics. instead of having a 14x180 Horizontal bar i would make it 14x1 so it streaches itself. If there are ends to it i make the ends seperate and streach the middle.
-This is when i put all my info it in. All pages on my websites tend to look the same because of the types of sites i make. I just copy and paste the same design over and over again and put the info into each one according to which page it is.
-After eliminating load time of the graphics and putting in all the info i open up the code and clean it up and make it all purdy. This is normally when i extract things such as the menus and headers, things that are the same on every page and make them their own page and use Server Side Include to add them. This makes it alot easier when adding stuff to the page later.
-At this time i usually look over the site, decide if its worthy of publication, and then delete it. This step varies from user to user.
This is how i normally make my sites when its just Me, HTML, and some graphics. Recently i've been using PHP but i don't want to get into that :P BTW, I'm not professional, just a hobbiest, although i have joined a Webdesign company consisting of other hobbiests.
:p