Sending an expert to a remote site or a ship to fix a problem is a last resort.
Like, one of the first projects I worked on was diagnosing a malfunctioning valve where most of the work was finite element analysis on computers, but we still had to send someone to take measurements and temperature readings since the company that made the valve no longer existed (and I'm not sure how you'd ship something like that since it was very large and used with contaminated water)
You usually get much better results when you work in a well equipped lab and have access to the right experts. For anything non-trivial "replicate, understand, fix, deploy" is a much better approach. Not always possible, and when it is not going to site may be the only option, but it should be fallback, not primary path. My 2c.
I spend part of my time developing large, real time, visible systems and when things do not go as planned there is always a lot of pressure to go on site now and "just fix it". I have taken my lumps to learn that the right approach is to say "no, we will start in our lab".
I'll continue to consider it in the future.
My group used to have a list to sign up for going out on sea trials. I never got high enough on it to go. If you don't want to go, I doubt you would have to.
If a Naval unit has an issue, they'll attempt to reproduce it and develop a solution at a remote location. If they can't, they'll send an engineer across the planet to evaluate and fix it.
They do this even for not "critical" systems. I was impressed at that level of dedication.
It was this part that made me re-think whether or not I wanted the position. I wasn't ready to commit to being available to travel to the other side of the planet at a moment's notice if/when something goes wrong but I do appreciate the commitment.
The current rush to the bottom school of thought in cost-saving will have a serious detrimental effect on our military prowess. Sure, some people think that's a good thing but I do not.