Ok, so I have been looking at a lot of logos recently, all done by graphic designers. And in the majority of them, the only thing they have is a name or some "basic" text. I thought the idea behind a logo was to catch the eye of passers by and the attention of prospective clients. So again, here's my question: Why are the majority of logos just plain text or a spin off of plain text (stylised writing), with little or no imagery or picture base to catch the eye of people? They all seam to be the same and very "simple". I am just wondering why this is the case in almost all the logos I see.
You're making some very broad generalizations.
I'll make one too: There aren't any codified rules when it comes to logo design.
That said, I always like to quote the godfather of logo design, Paul Rand:
Ask most any Graphic Designer that's been around for a while and they'll tend to agree (at least mostly) with Rand's statements on what a logo is meant to be.
In response to your question, I think item #2 is key. A logo, itself, isn't meant to sell the product or service.
It should look good, and be aesthetically pleasing, but the task of selling is a team effort...it can't fall solely in the hands of the logo. There's the overall brand identity, the copywriting, the visual design of all other assets and materials, the marketing, the ads, the product itself, the user experience of the product, the service quality of the company, etc.
As for 'plain text (stylised writing)' lots of logotypes are that way, though the better ones wouldn't necessarily be considered 'plain'. They may be simple in form, or conservative in their stature, but typically they'll have unique elements to make them memorable--even if said elements are subtle.
To answer your question straight, generally the name of the product appears in the logo so people know what it represents. Given the logo may appear reproduced at small size, it makes sense to make the text large in comparison with the overall logo size, so the name is still readable. The maximisation of this approach is stylised or decorated text rather than text + separate elements.
Are there counter-examples? Yes, Apple, Nike etc. But generally they started with the name of the product as a major element and dropped it when it became extremely well known.
I think two big keys of logo design are versatility and durability.
Apple is a great example. Do you know what their original logo looked like? Check it out here if you don't. It's certainly artistic, but it's useless to build a brand around. Would that have look good on the back of an iPod? If you want to scale that down for a letterhead, how well would you be able to do so? If you want to use paint splatters on your billboards for your Nanos or bright colors for your iMacs, how well would that fit in?
The current logo for Apple is just an apple. It's well-drawn but pretty basic. However, they've built a powerful brand around it, and they can fit it into pretty much any scheme and it make it work.
If you're not a fan of Apple, The American networks ABC and CBS are good examples too. Though they doesn't evoke as much as Apple does, their logos have been in effect for about as long as television, and even though throughout their history they've been animated, gradient-ed, beveled, and colored differently, the core mark remains the same. That's great for brand recognition.
What's also great for brand recognition is including the name of the brand. Apple is really an exception, as is Nike. If you want people to get to know your brand, make the logo include the name. A classic example of this is Mobil - the logo is just the name, but it was clear, well-drawn, modern, and the different-colored 'o' taught people how to pronounce it.
There is plenty of room for pictures and imagery and symbols in the overall branding effort. And a lot of the best logos will often have a component that makes it unique and memorable (The arrow in the FedEx logo comes to mind here). But having a logo that doesn't do too much means that it can fit in a lot of different sizes, colors, and media, which gives your mark greater versatility and durability.
The beauty of a corporate identity is in it's application and the guidelines therein, not necessarily the mark.
The mark itself can be anything from a complex illustration to just plain ol' type. That is dictated by the concept underlying the branding. The larger identity system will include the mark, supporting typography, color palettes, and voice and photographic guidelines, among other things.
The complexity of the brand is usually manifested in campaigns over time, not in the logo itself. Thus, the logo should be adaptable to the climate at hand while retaining it's essential function as a memory trigger.
Maybe through a historical mindset:
Logos originate from the military world. In a battle, you have dozens/hundreds/thousands/hundreds of thousands of men fighting (based on the time of observation). Alexander might have conquered the word with a few hundreds of soldiers, but the British Empire's army sprawled over the world. If you know most of your comrades by name, recognizing them in a battle is easier. If you don't, you'll need identifiers: uniforms, flags... Chivalric times saw the nobility paint their shields and raise flags. The British Empire saw red uniforms and flags risen. The First World War saw colorful uniforms drop out of fashion due to them serving for target practice by the enemy... but flags stayed.
Commerce is a battle, with as much confusion as a military battle. Just as a soldier might only have a split second to recognize friend from foe, a customer often is exposed to a brand for a split second. Humans being language-oriented, text logos will tend to stick a little bit more in their heads. However, they also tend to be slightly longer to decypher, and once your brand is established you probably want to have a more pictural logo that's instantly recognized, and let people's mind make the association to the text behind the logo. if you see a silvery Apple, you immediately think of the name, and maybe even of "Think Different". The same way as a small unknown regiment makes a name for itself and its insignia becomes well known, a pictural logo needs to become well known through the company's products.
Using a textual name can help people focus on this, but also exposes you to some risks such as unexpected association: imagine a hotel chain called "red lighthouse" that for example would start existing in Canada. Sounds innocent enough. Of course, a red light house might mean something entirely different in New Orleans or Amsterdam... A logo of a red lighthouse doesn't carry this risk, but then again you could still use a combination of pictures that turn out to be perceived as offensive in some country...
Hence there are multiple ways: either go for a pictural logo first, and build awareness through success, or change along the way as many companies have. Or if you're Michael Dell and have a short name, use your name in bold black letters :p
Carrefour, second largest retail group in the world, uses a three color (blue, red, white) losange logo. It's instantly recognisable, carries the colors of France where the company is based, and the white part of it is a C... as in "C"arrefour. That makes it a middle-ground between text and picture, as well as a pretty abstract image-logo. It also prints perfectly in black and white.