Why brand matters to a first-time founder
Customers recognise a business by a set of signs and by what those signs lead them to expect. The name, the mark, the pack, the price, and the experience all feed that recognition. A logo is one sign. If the name means nothing reliable, a new logo does not create a brand. Reputation collects whether you manage it or not, and a bad association is still part of the brand.
Examples of brand
A maker in Stockholm sells flaked sea salt under the name Norr Salt at about SEK 45 a jar. Shoppers look for the name and the jar, and they expect that salt. The word mark is held as a trademark. A retailer copies the jar colour and not the name. People still ask for Norr Salt. The colour was never the whole of what they recognised.
Common misunderstanding
A brand is not only a logo, a colour, or a registration certificate. A trademark is a legal right in a sign. Brand identity is the design and the words you choose. Brand equity is the commercial value of the recognition. People can keep a clear association with you after a logo change, and they can ignore a logo they do not remember.
When to use it
Use the word when you mean how customers recognise and remember the business, not when you only mean the artwork file. Protect the name where the law allows, and keep the product in line with the promise. A side project with no separate name and no separate promise does not need its own brand yet.