[dale]

To clarify; TC is two sets of slicks and two sets of wets, so a change in weather conditions is covered. It's very rare to use all 4 sets. Normally wets sit in the pit box, doing a run here and there when there's a shower. Or the odd meeting when it rains all day. It's common to see wets with 4 or 5 different scrutineering marks as they last way longer than slicks, which I guess is similar off-road. I remember BB greens lasting for ages.

Only one compound of slick and one compound of wet. There's no need for multiple manufacturers and compounds, that just increases cost as you have to turn up with all the options, and test all the options.

So on the majority of meetings you just use 2 new sets of dry tyres, but have the wets ready if needed. If tyres were unlimited, it would be 6 new sets of dry tyres. If multiple manufacturers were allowed, then you'd have 18 sets of new tyres in the box for one meeting...