DM's Perspectives
When a DM sits down and designs the layout of a world, it usually occurs top-down and in the form of maps. This encourages DMs to process (and explain) every moment from overhead. And it makes the players view things from the same angle. Thus, the DM misses out on details that real people in the players' situations would notice.
When something wounds a monster or player, other players would be able to smell the blood. When a goblin fires an arrow at a player in the dark and nicks their ear, they won't know that it was an arrow until a few moments after they got hit. The first thing they'll notice is a sharp hot pain on their ear. They'll wince, and as they put their hand up to their ear and hear the arrow land behind them, they'll piece it all together.
As a DM, you have the most knowledge of your world. You're free to choose your perspective. You're not constrained to the perspective of an omniscient. Instead, consider imagining yourself as an invisible body walking alongside the party. Imagining the moment, look around you. Seeing only the things that the players would see, notice the situation as only someone would while standing where you are. A few examples:
What does the floor feel like to the players walking over it? Is the room they're in echoey? If they're in a dungeon hallway, is it narrow and claustrophobic? Do players take psychic damage for that or do they attack at a disadvantage? When a player encounters an enemy, are they looking up at the enemy? Or are they looking down? Does the enemy stink, does it slur its words, can you hear or see or feel its breath? When a PC blocks an enemy sword strike with a metal shield in a dungeon, does the ring hurt the ears of everyone nearby? What does a potion smell or taste like? It's impractical to address all these sensory experiences all the time when playing. But it's valuable to remember that these experiences can help immerse the player, as well as the DM.
By injecting life and personality into encounters, goblins and orcs suddenly stop being interchangeable to the players. Every fight is a different sensory experience, against enemies with different personalities, presences, and bodies, all which make for a more satisfying experience.