It could also mean you might be working without taking real life scale into account. Check your object dimension, if your object is huge or tiny, when you input a value on the bevel modifier, it will take your object dimensions into account, apart from your scale being 1, 1, 1.
For example, a bevel of 0.5 will look different in an object that is 2 meters by 2 meters in dimension, than in an object that is 0.2 meters by 0.2 meters in dimension. In the 2 meter object the bevel of 0.5 will be small but in the object of 0.2 meter the bevel of 0.5 will be big. So also check how big or small is your object, always work on real life scales.
Hope this helps.
