I think the word is:
I have a pretty sharp memory.
A log is usually a record of events that have happened, e.g. within a computer system, a ship's journey records, or just a diary or journal.
Preceded by a C, I am usually a hindrance.
A CLOG is a blockage, e.g. in a pipe, where the flow of water might be hindered.
But with a B instead, I can prove to be the opposite of that.
A BLOG might be a useful way for a person to post their thoughts, ideas and worries, in a way that gives them headspace. Additionally, many blogs contain useful information for others looking for instructions or help online.
It might get difficult for you to identify me if you add an S though.
Something that is a SLOG is difficult to get through...
But with an O, it should be fairly simple.
Placing the 'O' this time at the end (since it doesn't specify where this should be positioned), a company LOGO is generally better for memorability when it is kept simple!