With Candlestick Park it was the stadium being below sea level. Literally there was nothing that could be done about that field.

With Levi's, I'm guessing it's weather related just as much as anything else. It's surprising though because the weather in Santa Clara should be more consistent than SF.

Can't explain it otherwise. When they used Levi's for SB 50, the NFL brought in their own grass for the game like they do for all super bowls (even their own field turf for non grass fields). It was better for sure but not as ideal as Arizona, Houston.