Getting a backup QB

It seems to me that the really super successful teams over the last couple of decades weren't too worried about having a quality backup.

The Colts with Manning, Steelers with Roethlisberger, Saints with Brees, Packers with Rodgers, even Seattle with Wilson and of course the Pats.

I know the Pats had Jimmy G, but they didn't fight to keep him. Similarly, I know Cassell played well in that one season, but he only ever compiled one decent season after that.

It looks to me like all of those teams say, 'this is our man and we're not wasting money on a backup who isn't on a rookie wage because if our man goes down we're toast.'

It seems that Goff is durable and we have a great Oline (at least we did) so why not use the Draft rather than paying players mostly just on the basis that they have played in the NFL?

Just curious what you guys think and why I'm wrong!

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