Particularly in niche markets, it can mean missing out on huge numbers of candidates.
Here are some reasons why:
There's no spell check on LinkedIn
For that reason alone there are typos abound on profiles. Misspellings of Manager and variations are found on almost 2 million profiles. That doesn't mean people can't spell these words, it's just they haven't noticed the mistake.
That's a large pool of candidates to miss out on and these oversights are also found on heavyweight profiles at heavyweight companies.
Users aren't always looking for a job
and so don't attribute the same level of care when creating their LI profiles as they would to their Resume/CV. They're often thrown together in a few minutes without great consideration, unsurprisingly resulting in errors.
Many people put their profiles together using abbreviations. I've noticed this is particularly common among candidates in the Financial sector but it applies across the board.
There's the age old view of discounting candidates who "can't spell", but for me this is a completely different consideration on LinkedIn, for the reasons mentioned above.
Eminent misspellers include:
If these guys are still in work, in spite of an inability to spell correctly on LinkedIn, then that's good enough for me.