Extra spool?

[Outlaws]

What is the main reason for an extra spool?

I am just starting out and got a Lamson Litespeed (3-5wt), but Litespeed product line has been replaced with a new metal coating so I am wondering if I will regret not getting a matching spare spool right now while I still can.

[DUZBASS]

i only own a couple extra spools, they really only help when you are using a reel for 2 different rods, or if you have something like a floating line on one spool and a sinking line, or sink tip on the other spool, for a 5 wt I would not bother honestly, save your money for waders, vest, net, flies, etc.

[Questor]

Here are my applications for the few that I own:
1) two reels have extra spools, one for floating line, a second for a sink-tip line.

2) one reel is used for two different rods. Each spool has a different line weight.