A fly fisherman on a cold mountain stream and a big-game crew on a tropical reef are fishing completely different locations. Doesn't matter how good you are — the stream doesn't hold marlin, the reef doesn't hold rainbow trout. Both can be bloody beautiful days, just on different terms.
Your solar panels work the same way. Winter in Scotland and summer at the equator — different locations entirely. Same panel, completely different physical ceiling.
Most apps score every day against the tropical reef. No wonder your perfect day reads 40% and you're thinking the gear's stuffed.
Solar Spotter scores your day against the location you're actually in.
Different locations. Both bloody beautiful days.