The trick to doing works for hire is to recognize that you are not the final arbiter of quality. More importantly, your task is to apply your skills to the best of your abilities in service of what they want, not what you want. I love what I do and I've done some amazingly stupid shit. Eight plant mics to perfectly capture the sound of a miniature schnauzer running around for two hours. Two hours of voice work and processing to perfectly capture the essence of a gelatinous, transdimensional Snooki. Painstaking, mind-numbing clip finessing so that the Vegematic edit perpetrated by a director that should know better sounds seamless, despite the utter inanity of the interview. But I do it damn well, because they're paying me for a task, and that task is their choice, not mine. The minute I agree to take money for it I'm subverting my judgement to theirs. The only way they can screw up your work is if you are incapable of giving them what they need. Otherwise you're doing your level best to conquer a task that, given your druthers, you would not undertake. And I've had shitty editors fuck with my work because they're too rushed and poor to get another pass out of me - but the stuff they're paying me for, they get as close to perfectly the way they want it as I can get. Do I try to bring them over to my way of thinking? Every time. But I don't get too worked up about it because I'm renting out my skills, not my judgement. If my client wants a Jack and Coke, and he's buying my whiskey, I'm not going to begrudge him one bit. He can pour that shit on the floor for all I care. If I enjoy making whiskey, my joy is making whiskey and my payment is giving it up when I'm done. I'll go one further. If my client tells me he's gonna mix it with Coke I'm going to craft him some not-sweet-enough, way-too-heavy-on-the-bite whiskey so that it'll balance out his cola better. 'cuz I'm a professional. I think it was David Brin who said he didn't care how bad The Postman was because the novel still existed. You do the work you do because you're good at it, and if your clients don't want the work that turns your crank, turn your crank doing something else for yourself. People paying for drivel allow you to bottle the brilliance for free. Both Wesley Snipes and John Sayles support their arthouse habits with Hollywood schlock.
This is really the essence of the idea. Follow your bliss, and all that dippy shit, but know that your work is only part of a larger whole, and you need to be able to do good work, then turn your back on it and move on. There's a preciousness to things nowadays that is a bit galling. All work is done in steps, as a part of a system. Enjoy your work. Do it well. Take pride in a job well done. But do not treasure your work, or value it higher than the person that paid you for it. That way madness lies! :-) Yeah. People like working with me because I'm a personable guy. I know much better writers who don't get the work I do because they are hard to work with. Be good. Be patient. And be willing to release your stuff into others control. The trick to doing works for hire is to recognize that you are not the final arbiter of quality.
More importantly, your task is to apply your skills to the best of your abilities in service of what they want, not what you want.