I have an acquaintance, "Alice," who has been fired twice for witnessing at work. Well, that's how she explains it. Perhaps a better explanation may be that Alice's approach to evangelism is "in your face."
If there were a caricature of an evangelical on the popular show The Office, Alice would fit the bill perfectly. She embodies all the negative stereotypes our culture has about evangelical Christians: she's judgmental of all things secular, she frequently refers to "the Lord" in any and all conversations, she gets so pumped up when talking about her faith that her behavior borders on the bizarre, she's completely (and purposefully) out of touch with culture, and she regularly asks co-workers and customers alike what would happen to them if they got in a car accident while leaving the store. Would God let them into heaven or would they burn in hell?
Alice considers any attempt by a supervisor to get her to "tone down" her evangelism at work as persecution, spurring her on to even more zealous proselytizing. In a word, Alice is obnoxious.
None of us want to be like Alice, so we hop on the pendulum and take a ride as it swings far in the other direction. Instead of going overboard with evangelism at work, our efforts to share our faith may be more "subtle" and "nuanced." They may be so subtle, in fact, that they're imperceptible.
Or we may be waiting—for the right opportunity, the right relationship, the right line of conversation. The trouble comes when we're waiting for a really long time … like years.