How does the practice of assigning IP addresses on a home or small office network make troubleshooting easier?
There is information here:
The primary benefits are:
You don't have to lookup the IP of the device for basic testing (ping, telnet, ssh) or to identify the origin of unwanted traffic.
Your network is not vulnerable to rogue DHCP servers.
Your devices will or should be online as soon as the hardware port is online (initialization and negotiation of switch ports can cause DHCP requests being dropped).
Also technically you can limit the use of internal services to specific IP's to prevent (or at least make it harder) for unmanaged or unwanted clients to (ab)use them e.g. file shares.
It is basically like naming your computers; it helps in figuring out which device is connected with which IP address. When you can easily find the computers by IP address, you can weed out the working devices and IP addresses then try to focus on the actual area of concern. Other devices that connect to the network would use another IP address so you can tell if it is one of your devices or not. You can also set it so only the devices you select can connect to your network, blocking out people you do not want on your network.
you have to ask the provider if you want to assign different IP address to each computer.
By assigning, do you mean assigning static IP addresses? If so, it make it so you know the IP address without having to run ipconfig.