What's with these cordless mice? I think I'll go back to corded.

[Paper Roses]

My computer guru suggested, several months ago that I switch to cordless mice for my PC and Laptop. Every time I use them...OK, not every time, but too frequently I have to replace the batteries. I asked at Staples, where I bought them and was told they should last 18 months without a new battery. Nuts! I have to replace them every week or so. I don't use the PC or laptop all day. My use is occasional. This is driving me nuts. Is it me or the nature of the beast? I think I still have my cord mice. I never had a problem before. Are these things useless? My guarantee has expired so if they are defective, my loss. One is Logitec, the other is Microsoft. Phooey!
Your opinion would be appreciated.