If you're striving to do something, it means you haven't accomplished it yet. Your clients pay you because you are an expert, not because you are striving to be one.
We strive to create the best customer experience.
We strive to make your wedding planning process enjoyable.
We strive to give you photographs that capture your day.
We strive to give you and your guests a fun experience.
You either are an expert or you aren't. You either know how to make what you are selling to clients happen or you don't.
Using the word strive (or any of its synonyms: endeavor, aim, etc) absolves you of responsibility for the outcome because it positions you as an amateur who hasn't yet figured out the ropes. It also tells potential clients that you don't fully believe in what you have to offer and makes them hesitant to trust you with their money and, more importantly, the creation of some of their lifelong memories. (Related: if you're feeling like all your clients are micromanagers, check your marketing copy for words that tell them you don't trust your own talents.)
There is nothing wrong with consistently looking for ways to improve, and true experts know that there's always more to learn. Deleting the word 'strive' from your marketing vocabulary also doesn't mean that you're promising unattainable perfection. It simply means that you're a professional and know how to deliver consistently.
Stop downplaying your talents and own your expertise. Your art will be better for it, and so will your sales.