A student of mine asked me this question today: "How do you keep your vision (as a writer) intact and continue to have a conviction behind your chain of thoughts when you know that the depiction and sensibility of the film (by the director) is going to be different than the script anyway? As a writer, does this bother you... and if it does how do you fight it, and still maintain the quality of the product?"
I can very confidently tell you that the issue mentioned above does not bother me at all. But I understand that there will be writers who will be struggling in this regard. I'll share my take on it. And I'll present it in the form of certain facts that I think a writer should keep in mind:
1. Accept that you are a writer, and not a director: A writer is not naturally capable of directing, unless he has those qualities in him. Creating a world on paper in solitude is difficult but also very different from re-creating that world working with hundreds of people, getting things done in the midst of chaos, and especially dealing with technology and egos of people. So, the writer should understand that he or she, despite being the creator of the story, need not be the best person to direct it.
2. Your script is your film and your only opportunity to seek fulfillment: If you were a famous popular novelist, and you knew that the current novel you are working on will definitely be made into a film by someone, you do not start making the film and doing the shot division and meeting composers for the musical score. You do what you do best - writing the novel. And even if you visualize things, you have accepted that the film-maker might change them, and that this novel alone is your own space where you can do what you want to. Similarly, a screenwriter should write the script he wants to write - and make that film in his head. But he should know very well that the film from his head will be 'remade' by the director. That does not mean he should feel demotivated. The script is the writer's space - and he should do all that he wants to in that space. Consider this - the script is the only opportunity for the writer to 'make his film'. So, he must use it uninhibitedly. This is the only version of the movie he can say he created on his own and take pride in. (The only exception to this is a scenario when the director is attached to the writing process and you are writing to fulfill his expectations. In that case, you have to make a choice whether you want to write as per his instructions, which, according to me, is completely fine and a fair professional decision, or you want to convince him to let you write your way.)
3. Detach: Once your script has been approved, the writer should detach himself from the process. He should learn to let go. Mothers and fathers let go of their daughters (and in some cases their sons). Teachers let go of students. Artists let go of the art-works they have sold. Even directors, at times, let go of the films they have made. So there is no reason why a writer cannot do it. This is a part of his job. If he cannot do it, he should write only for himself, or better, write and keep the script in his closet. However, detaching is not the same as disowning. Depending on the film that is being made, and the way the director is re-interpreting the script, detachment can be of different levels. You can be present on the set and help the director with all he needs, knowing very well that you will have to let him take the final call. Or you can choose to never visit the set, and possibly even not watch the film when it is out. Between these two ends is a wide spectrum, and a writer finds himself attached (or detached) with the film by trying to find that place in the spectrum that suits him as per respective projects. In any case, I think the trick is to trust the director initially. And if things are not happening the way you had visualized, wish him all the best and detach. Start working on the next script, the next 'film in your head'.
4. You are not alone: All creative individuals working on a film struggle to achieve this balance that we have been talking about. A cinematographer might have a certain vision and style that he willingly modifies to suit the director's vision and style. An editor does the same. Even actors wish to work within the director's interpretation of the characters, or at least seek approval from him regarding their interpretations. Musicians, lyricists, choreographers, production designers, sound designers - all strive to achieve that balance. Film-making is a collaborative process and the director is the head of the pyramid. If all creative individuals can come together and become a part of his 'film', there is no reason why a writer should keep sulking in a corner. Perhaps the only reason would be that writers are most used to solitude, and sulking in a corner is something that comes naturally to them. But otherwise, they should understand that they are not alone, or are being 'sidelined' by the director.
In the end it's all a matter of readjusting expectations, and constantly doing so. Being a part of a team and maintaining your individuality and giving the best from your end is a question of character. It is not easy. But so is life. If wedded couples can do it, if sportspersons can do it, if soldiers can do it, why can't a writer - who is doing one of the most difficult jobs on earth? How he or she manages to achieve that detached attachment will finally depend on his or her character and priorities. A start, however, can be made by accepting some facts, like those mentioned above, with faith and the right spirit. After all, "A man's gotta do what a man's gotta do." ( from Takashi Miike's 2007 film 'Sukiyaki Western Django')