Long sightedness, or hyperopia, usually affects our ability to see objects that are close to us clearly but may also affect our distance vision depending on the degree of long sightedness we have and our age.
When a long sighted eye is relaxed and looking towards a distant object, the light coming from that object would be focussed behind the retina (the light sensitive layer inside the eye) and the object would be blurred. The closer the object moves towards you the more out of focus it becomes.
This is because the eye is either shorter than it needs to be or the cornea at the front of the eye is not as steeply curved as it needs to be in order to focus light at the correct point inside the eye.
We have the ability to adjust the focus of our eye, like focussing a camera, to compensate for the eye being long sighted and to allow us to see clearly.
When we are young, we have lots of focussing power in the eye and can often overcome our long sightedness without glasses.
However, as we get older we slowly lose this focussing power and it becomes more difficult to keep our vision clear. As it takes more focussing power to see close objects clearly, it is close tasks such as reading that become more difficult first.
When we will need to wear glasses for long sightedness will depend on how long sighted you are, how old you are and whether it is causing any difficulties such as headache, eye strain or blurred vision.
It is entirely normal, that as we get older, we will become more dependent on wearing glasses to correct long sightedness. This is not evidence that glasses have made our eyes weaker in any way but is a result of our natural loss of focussing power that happens in all eyes as we get older.