Are cable “upgrades” just as likely to make your system sound worse?

Keep in mind, the quality of your components and music files can impact what you hear. Many times high quality cables can be more revealing. This should not be confused with being bright. It’s the old garbage in, garbage out theory. There is a synergy between all three. 

There is no "absolute sound" that everyone would agree is perfect. Therefore it's all about listening preference or bias. I think most here would agree that cables can and will make a difference in our audio systems. Whether that difference is an upgrade (preferred) or not is totally up to the taste of the individual listener. The listener who "got his bass back" by re-installing his less expensive cables may have muddied his system or subtracted detail to the ears of another.

Choosing cables is all about synergy with your room (#1) and your equipment (#2).

When I decide to upgrade a cable, I usually test out 4 or 5 (returnable) cables before choosing.  Give them all at least 100 hours of break-in time and test them with ~10 tracks that you are VERY familiar with that test sound stage, tonality, transparency, speed and emotion.  The one that makes you just want to keep listening is the winner.

Silver cables are definitely the best to me, but good ones (high purity OCC) are very expensive.

The worst part is cables do need ample burn-in time. Patience is key and buy only good reputable cables so resale will be easy because there is usually no way to properly test a cable within the return period policy.

Taking the OP’s question literally: "Are cable “upgrades” just as likely to make your system sound worse?" the answer is a solid "NO!" They are not just as likely to make your system sound worse." In fact, it is highly UNLIKELY that they will make your system sound worse.

To quote William Low: "Cables can’t make a system sound better. They can only make it sound worse. It’s all about damage control." My take here is that the "perfect" cable would be NO cable. Anything in the signal path will degrade the sound to some degree. We’re just trying to minimize how (badly) they mpact the sound.

To address those who do not feel that cables make a difference, I would submit that it is impossible for 2 cables with different materials, geometry, gauge, dialectric (insulation), shielding, termination method, termination, etc. to sound the same. I’m not asserting that there will be a sledgehammer difference in those cables, but there will be "some" difference(s).

Comparing cables:

One attribute of cables can be dynamic compression. They simply hold back the energy presented to them. When "better stuff" is put in the signal path, dynamics can get more pronounced (louder). This may, or may not, be a good thing depending on the system -- and, the listener. "Opening up the top end" sounds like a great idea. Except when it reveals "warts" in the signal path -- or issues with the room acoustics. Or, the changes are simply not appealing to the listener. So, we decide to "dumb it back down" because the cable is "too bright" or "too forward", etc. I’m not saying that this IS the case in every system, but it could be the case in some.

As some have suggested, cables need burn in time. So, your first (negative) response to a cable may be a bit premature. Patience.

Yes, upgrades can definitely create "mission creep", and present the perfect storm in our pursuit of better sound.