This is usually not so good, but it also makes the image bright and contrasty, which is. Low-power images have wide fields of view that take in lots of stars. The steepness of the funneling is the focal ratio. For most refractors and Newtonian reflectors, the focal length determines the tube length. That, in turn, affects the height of the mounting and, therefore, its weight.
Telescopes have dozens of qualities to optimize.
But no telescope is best at all the things telescopes can do. You can optimize some but inevitably at the cost of others. Principles of optics and physics extract a price for every gain. So telescope design is the art of tradeoffs. Every time you gain something, you lose something.