How do you know if you are an annoying twitter

Twitter has become huge and super popular. I my self am still unsure to what is was created to do but I use it to promote my Etsy shops. I have build up a decent following and think that I do well with it. However how do you know if you are linking people to an interesting place or if you are just annoying them. I feel that if you post only for your selfesh needs that in time people will get annoyed maybe even bord. They might just ingor you tweets but worse they may just quit following.
I think sometime we have to step back and look through the window with the on lookers to get a true propective of what we are doing. Twitter is a great tool if used right. So ask yourself why, what, where, who and how. Why do I twitter, what am I trying to get out of it, who am I twittering for, where do I want twitter to take me and finally how do I plan to use all this information. I asked myself these same questions this very morning. I am sure we all have different reasons for being on twitter. I want to promote a shop and a business and I want to build interest in them. I also want people to follow me and click on my links. So I also post interesting things not for me but for my followers. Sometimes when I see something funny I post on twitter. I also do this with good articles on running a successful business or tips to a healthy, happy life. This way I am not just spamming all of my follower but helping them to succeed in their endeavours. This way they are excited to see my new post and eager to click for the info I have provided. I think if you take a bit of these tips and apply them to yourself you will not only gain more followers but you have quality ones.