I share your opinions, and empathize with your frustrations.
Some of this is absolutely due to the lisitng agent. But, not all of it.
First.....about choosing a listing agent.
FULL SERVICE: Sellers need to ask questions before listing their properties. While it's great to list with your friend, or Aunt Mable, this is an important financial decision. While it's great to get referrals, it is also important to review your goals and expectations with the referred agent to ensure that it is a good match. Too many sellers do not ask questions in making their decisions to list. Some listing agents take a hands on approach to what happens to the listing beyond simply the MLS; others submit to MLS only and rely upon the MLS and/or their broker for distribution and marketing from that point forward. It's certainly fine for an agent to align with a broker who supports the listings and makes sure it is widely distributed (with detailed info, multi pics, etc.); but a listing agent should be able to explain to the seller where and how their property will be promoted. For as long as sellers give listings to agents without expectiations, this will happen. When sellers decline to do so, it won't.
LIMITED AND DISCOUNT SERVICE: Sellers have the right to choose limited or discount servicee. There should always be a relationship between what you pay for and what you get, when it comes to property lisitngs and representation. Sellers who choose to hire a limited service company, with full understanding of what they will receive, are entitled to make that choice. While buyers may find this frustrating (and I fully agree w/ the buyers who do find this frustrating); please do understand that a free market society allows the options of varied service levels and fee schedules. Choice is a good thing. While I personally believe that full service with high level marketing materials, hands-on regular involvement from the lisitng agent, and committed representation is the best way for a seller to go, I fully respect the right of all sellers to make their own choices. Many sellers believe that simply getting in the MLS is the way to go, and look for the least expensive route to accomplish that. In many instances, the sellers will net less, and the savings comes with a hefty price tag in a lower sales price for exactly the reason you describe. You, as a buyer, find it frustrating, and bypass these lisitngs.
Thank you so much for sharing. I empathize with your frustrations. I sincerely wish that more sellers would demand more from their agents, and all would be better served as a result. Agents who did not care to deliver would find another line of work. Buyers would be better served. Sellers would be better served.
There are a number of compromises to data integrity in aggregating data from so many sources. There are 100's and 100's of MLSs, all with different database structures. There are data feeds trying to transfer data in private uploads to various sites. As a broker office, we send all of our lisings for any of our agents to over 30 websites. Some of our agents comprehensively understand where we send the lisitng data; others do not.
We have office staff who constantly spot check our listings, and it is expensive for us to absorb this expense. Our office staff each have a handful of sites that they monitor. They periodically pull random listings of ours to make sure pictures, data, tours, etc. are complete. When it is incomplete, we notify the tech dept of where we send the data and ask them to look into it. There are tech glitches....I see postings on Trulia Voices where an agent or seller asks about their lisitng, and Trulia responds back on the thread offering to look into it. There are just tech glitches.
Other places that upload lisitngs do not want to allocate space on their servers to house lots of photos. So, they only accept part of the data and part of the pics.
Thank you for sharing your thoughts. Please know that I fully agree with you in your desire to want lots of pics and complete descriptions.