the barrier is closed formats and broken standards, like it always is with MS.
A document created in MS Office is not always going to work in OpenOffice.org, Microsoft even change the file format between versions of the software, as an incentive for MS Office users to "up"grade, but also to deter projects that would like to read and write to Microsoft Office file formats. Even if it does open, it may well not look anything like it did in MS Office, and that does put people off. Sometimes the difference is irritating enough to really get on your nerves.
This is because MS, the owner of the de facto standard in office software file formats, have decided to manage their formats in this way. closed spec to force everybody else to guess how they work and change the spec every couple of years just for a laugh. Instead they should use proper open standards and everybody'd be happier.
By comparison it would be like if a small country already had a functioning government and economy and then a large country like the US imposed sanctions or sent troops in to "sort everything out" basically so they can keep control (of the global economy in the case of the countries, or of the market in the case of the software company). When you look at it, it's just selfish and nobody benefits except the large country, or in the case of MS the large company, same thing in a lot of ways.