Why would you run video through a processor?

How could a processor do anything but degrade your picture. Why not run the HDMI cable straight into the TV?

So that you can control everything with your processor remote especially if you have more sources than inputs.
On screen menu's, internal HQ video scaler, convenience, ease of wires in walls, no noted signal degration....do I need to go on?
I am a purist and run direct wires but I can see why some circumstances other options would be better.
trick is to bypass the processor if you have better chips in your players or your display

biggest problem i have found with the in-processor chips is that they are global - one size fits all meaning that all of your sources are processed identically - obviously BluRay and DirectTV don't have the same needs.

Beyond that I totally agree with the other posters. Its just a lot more elegant way to cable your system. Run everything to the processor then one cable to the display. Can be a biggie if you have a long run from the sources to something like a ceiling mount projector.
Depends what kind of processor you are talking about... if you mean a HT processor, then maybe not... or maybe... depending on how good the chip is in the processor versus the source.

If you mean a video processor, then the answer is that it will most likely improve pretty much every signal you through at it (much better technology than what you will have in most sources or TV/projectors). I'm using my DVDO VP30 for all my processing (digital TV, DVD, HD recorder etc.) plus HDMI switching and extracting the digital signal as coaxial to my PRE/PRO. The improvement is obvious to anyone!
You guys are missing the point.

IF you don't run HDMI through your processor you will never get the uncompressed codec of DTS HD Master Audio and Dolby TrueHD, and if you haven't heard them, then you just simply don't know what your missing.
Kenny is correct. In addition you only have to use one input on your TV. Which means one long cable run, you never have to change inputs on the TV(change inputs on processor and TV displays source)It makes the system much easier to use especially for wives.
If your player internally decodes the advanced codes, you can run the HDMI for video direct to the display and the decoded 5.1 LPCM stream via digital (coax or toslink) to your processor.
Thanks for the responses.
I didnt miss any point as the OP was talking about the picture and nothing more. Besides you could still go straight to monitor for video and use multi channel RCA connections if player has internal decoder for advanaced audio.........like I said, no point was missed just trying to keep it "to the point".
The answer involves more than video. HDMI is the preferred method for SACD, DVDA, DTS-HD, and all other formats if it can be used. Some processors actually improve the video depending on the source and the ability of the processor.

you can only pass DD and DTS via coaxial or optical, all the uncompressed formats DO NOT GO over these connectors. They have to pass over HDMI or via 7.1 analog connectors. If you are running your gear this way you have never heard DTS HD Master Audio or Dolby TrueHD.
You are right. I was getting confused with 2 channel PCM which does go over the optical or coax. I run two channel HT so I just use coax to transmit decoded PCM from my player to my Wadia although to hear DTS HD MA I'll have to upgrade my player at some point.
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I am a total HDMI convert - the thought of ever spending the money to buy 7 premium RCA cables, plus the thought of the the effort to route and dress them to avoid the large number of wires found in most HT rigs has made a believer out of me

and it sounds better - what's not to love