Sometimes people correct LS' spelling on Twitter and reacts in the most rude, unnecessary way! Have a look:

Lord Sugar @Lord_Sugar · Sep 13
“@MrNiceGuy_2009: @gra4ham *Can't*”......... You bloody big head you and your type make me sick . You should drop the a and replace with u

How nice of him to call someone the msot rude word in the English dictionary just because of spelling. Later on the same day, he called someone a tw.. (****)

Lord Sugar @Lord_Sugar · Sep 13
“@gra4ham Sending photo of food. bloody eat it. We aren't interested. I don't tweet photos of my food.”.....not my food tw.. Cant you read

And yesterday evening he was not very nice about the X factor crew:

Lord Sugar @Lord_Sugar · 23h
X Factor Is this top cringe watching Cheryl and Mel dance round Simon. Do the producers really think the public are so thick
Lord Sugar @Lord_Sugar · 23h
x-Factor Cutting out the adverts and the crying grannies , parents and sob stories in general you can cut it down to 15 mins with SKY+

It seems LS really does have a rude nasty side. And even if he does, why the hell show it on twitter, over spelling?!

It did get a bit much for me where I considered unfollowing him at one point.

But then I saw him talking about twitter and he had his usual dry sense of humour about it, especially about twitter trolls. So now I take everything he tweets as slightly tongue-in-cheek, like when he's in the boardroom and giving someone a blasting. The words sound harsh but he's got a certain glint in his eye that he's putting on a bit of a performance to make things more entertaining.

I see where you're coming from, but it's never really acceptable to allude to the word c*nt referring to someone even if he sees it as tongue-in-cheek. Anyhow,this won't stop me watching, but his Twitter behaviour does lower my opinion of him. Anyhow, only a few weeks till the show returns! 8th of October I think

He called my brother a prick on there once. My brother was genuinely delighted.

I quite like it that he's not shy about saying what he thinks. There aren't enough people like that, and I feel like he's a nice person underneath it all. I think you can be quite sharp and even slightly aggressive on Twitter without it resorting to nastiness.

I do find it amusing how addicted he is to Twitter though! He updates it about twenty times a day, I think.

You like that he calls please c*nts on Twitter? Think about what you've said there!

And it is nasty.

To be honest, people who correct others' spelling and grammar online intensely annoy me also, so I can't judge LS too much for his angry response. I mean, doing that is very rude in itself, and always comes across (to me) as the person trying to feel all superior. Some people do it on here too, and I never fail to tell them how ridiculous I think they are. I don't call them the C-word, though.

As for his X Factor related posts, they don't seem all that rude. I've seen a lot worse on here.

I'm not saying he's never rude, just that the specific posts quoted in the OP don't really bother me all that much.

I stopped following him this year because he's constantly plugging some product or other (and not even products manufactured by him)

lol a former follower tweeted "LS thinks he's f**king Pearl & Dean"

He's a complete tosspot one day he'll mouth off to the wrong person.

Well, it's not how I'd go about things myself, but there is a difference between insulting someone in a malicious context and swearing at them because you're annoyed at them, and I would consider Lord Sugar's approach to be very much within the latter category.