Brand and branding
Way too often, you hear someone say that they are trying to improve their brand, so decide to update their logo. This helps keep logo firms and print shops in business as new letterhead and business cards are printed, but generally wouldn't do much for a company's brand.
My definition of brand: what people expect from a company. What they get, type of quality, price, level of service, how the company interacts with the community, etc. that people expect are all part of this. The term 'people' is vague on purpose, as it is not just customers or prospects, but also employees, suppliers, the community, etc.
So branding would be the process of trying to change these people's perception of the company.
Changing a logo will not really change what people expect to get from the company. You do this by changing the product and service and how the company interacts with the outside world.
Did come across an interesting brand situation. In Belmont, CA, there is a restaurant called Habibi. The restaurant's slogan is "A taste of Asian Cuisine". Middle East is also considered part of Asia, so the perception of what I was going to receive was Middle Eastern food.
But actually, it is South East Asian foods - a mixture of Chinese, Thai, and Vietnamese. So the name is working against the brand. And this shows up in their Yelp reviews - those who went looking for SE Asian foods rated them well, but those that thought they were getting Middle Eastern foods rated them poorly.
So, it is good to make sure that logos, names, slogans, etc. are not working against your brand. But, beyond this, I am not a believer that changing a logo or similar can really impact your brand.