Fast paced Gemini is ready to move on from problems and arguments almost the moment after they've happened, while thoughtful Pisces can spend longer ruminating on the issues. This leads to frustration for Gemini, who would prefer if Pisces just moved on and lightened up as fast as they were able to. It also hurts Pisces, who feels that Gemini dismisses their feelings and doesn't take them seriously.
Both of these signs find it difficult to commit to relationships, which is yet another obstacle standing in their way. Gemini is obsessed with moving onto new places, projects, and people, while sentimental Pisces can lose themselves in nostalgia. This means the couple are rarely ever in sync with life goals and committing to something more serious is tough. We totally see where they're coming from - best not to try this one at home!