Each Ace in tarot represents the purest form of its suit. If you believe in the existence of a spiritual world alongside this material one, then each Ace symbolizes unadulterated energy before it comes into form in the physical world.
But once any energy becomes manifested in the material world, there's some level of distortion that happens.

When brought down to earth, emotions are no longer pure – they're now filtered through our lens of self-consciousness. We decide what we want to feel and what we want to push away. And some things we don't even know we're feeling, because we were never taught to acknowledge them.
Once an emotion mixes with the other elemental energies – thought, action, and desire – it's no longer just something we experience. It's something we react to, either turning away from it and rejecting that part of ourselves, or trying to get more of it and becoming upset when it's not happening the way we want it to.
It's a skill we need to relearn. We need to practice having a healthy relationship with our emotions, instead of thinking they need to be fixed or transformed.
You don't need to do anything to your emotions, other than acknowledging they're there and getting curious about what brought them there.
Each Ace provides a unique gift acting as a cornerstone forming a safe and strong foundation – Cathy McClelland, creator of The Star Tarot.
Each Ace is a foundation in and of itself. And when all four come together, they're the foundation of a healthy inner world.
If it comes up in a reading...
Here's one of many ways to reflect on the Ace of Cups. Ask yourself, "How do I participate in the distortion of my emotions?"
When I'm sad, do I collapse into it and throw myself a never-ending pity party?
When I'm angry, do I reject that part of myself and rationalize my anger away? Or do I over-identify with it and do things that I later regret?
When I'm ashamed or embarrassed, do I become mean and cruel to myself? Do I double down on the shame and convince myself I'm unlovable and unworthy?
When I feel stressed and overwhelmed, do these feelings drive me into a panic because I believe that means I'm failing at life? Do I get stressed about being stressed?
Think about the last emotion you knowingly participated in distorting. How could you have handled it differently? What experience did you lose out on by reacting to the emotion, instead of making space for it? What can you differently now?