Linseed oil (both raw and boiled) darkens in the absence of light. That is, it darkens in the opposite conditions than those affecting most finishes and woods. These usually darken when exposed to light, especially high UV sunlight or fluorescent light.
Take a look at the accompanying photo of two cans of linseed oil in the process of going through their darkening stages. The can on the left shows fresh overspill, the slightly yellow color you expect from linseed oil when you are using it. The can on the right has been stored in a dark cabinet for several years, and the overspill has darkened significantly.
So what can you learn from this that is useful? That a linseed-oil-finished object will darken in time, especially if it is kept in low-light conditions. This can be an advantage on some woods such as bird’s-eye and curly maple, highlighting the figure, and on cherry and walnut, producing a warmer color. But it can be a disadvantage on “white” woods that you want to remain white, such as maple and birch.
To get the darkening effect along with a more durable finish than linseed oil, apply a first coat of the oil, let it cure thoroughly (maybe a week in a warm room), then apply the finish of your choice.