My router allows me to select channels 1-11 or auto. I have seen numerous posts in other forums where channels 1,6, & 11 were recommended. But never an explanation as to why auto is undesirable.

Is there any reason not to use auto and let the router select the best channel?

My understanding is that setting it to auto will simply pick a channel with no influence from the surrounding networks. Imagine if every single router within distance accidentally selected channel 11 to operate on. Becomes a little clusterred and your connection will most likely intermittenly drop.

Setting this to 1, 11 or 6 is just as a risk. If everyone sets it to these than you run into the same issue.

The idea is to optimize your wireless by selecting the least used channel you can. There are programs out there that will tell you what your surrounding networks are using and you simply select a channel that is used the least.

Now, some routers now-a-days actually account for new networks and changing networks and have a feature that changes your channel based on these new/changing networks to always utilize the least utilized channel.

I have never had an issue with mine being set to auto and I have 5 networks in range of my laptops.

A simple Google search will explain all this in greater detail as I am unsure of your comprehensive level when it comes to this so I left it simple.