The way that the majority of limited games play out is that from turns 2-3 onwards, both players are generally making one play each turn that advances their position in some way. If this carries on indefinitely the game is almost certainly going to be a very close one. However, in the real world this does not tend to happen. At some point a player will pass a turn without making a play in the same turn cycle that their opponent did play a relevant spell. Another possibility is that a player did play a card that impacts the board in their favour, but their opponent played two! One more is that a player played a relevant spell and while their opponent did also play a spell, it had little to no influence on the current board state.
These moments are the tipping points in the game that I like to call 'Tempo Swings'. A tempo swing essentially happens when one player makes a larger number of meaningful plays in a turn cycle than their opponent. I have found that a good yardstick is that if you have achieved a favourable tempo swing two times more in a game than your opponent and held that advantage over more than one turn, you are very likely to win.
If we take this theory to heart our goal is to both try and get cards into our deck that allow us to create positive tempo swings and also play in such a way that we open ourselves up to causing these situations for ourselves, whilst attempting to prevent our opponent from doing so. I must stress that you cannot simply just cast any spell or activate any ability and call it a meaningful play. You can only count actions that have a reasonable positive impact on your game plan.