bath tile grout

We have a tub where the surrounds are ceramic tile. I one or two area the grout started to pit a little. It started as a very small pinhole or two, now it's about 1/4 inch. My two questions are:
Is the easiest but right solution to just scrape out all loose material in the area and put in new grout?
What can I do to prevent this from occurring again, or is this just the maintenance involved with having a tile surround?
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grodenhiATgmailDOTcom wrote:

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