IT forced password changes => weaker password

Every time my company's IT forces me to change my password, my password becomes weaker.

At least, the password(s) that I actually have to enter by hand, manually.  

Frankly, I don't care about weakening the passwords for my company accounts.  After all, it's their IT department that is enforcing this obsolete policy.

But it is annoying that company IT also forces me to change my personal password on my personal machines that I use to log in to company email and VPN.   Those personal passwords start out really string, but get weaker every time IT forces me to change them.  So it's my personal security that is being messed up by company IT.