Before Sometimes even one motivated person can bring about a big change. After Sometimes, all it takes is one person to make a difference. Notes Inserted a comma after 'sometimes' Changed the sentence to pack in a punch.
Before --> The challenges of geographically spread partners, distributed knowledge and expertise, language and cultural disparities, etc., means we’re partaking in an age where education systems are weeding out some age-old norms. At the same time, it’s getting harder to source, manage, motivate, and retain talent while controlling costs. After --> The challenges of managing geographically spread partners, distributed knowledge and expertise, language and cultural disparities are manifold. It’s getting harder to source, manage, motivate, and retain talent while controlling costs. Notes: The 'before' version is not parallel. It is rather unwieldy. So I cut out the phrases that didn't add to the sentence.