Trees come in Two general shapes.  Excurrent ( conical shape)  and Decurrent (Canopy or Spreading trees) .  Homeowners who  have limited yard space may want to avoid larger trees and especially large trees with spreading canopies.  Spreading trees  have the following disadvantages

 

•  They extend over neighbour's properties.

• They often produce too much shade.

• The limbs extend substantially from the tree core and are prone to breaking

•  they tend to be more prone to storm damage .

•  They extend over houses , sheds and garages and become a hazard .

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 In Ontario, a common tree that ends up in people's back yards are Silver Maples because they grow fast and have beautiful fall foliage.  However these trees, because of their growth strategy (being a pioneer species), are prone  to have multiple leaders.  These leaders grow away from the tree center as they compete for sunlight; And as noted above, physics take over and they are susceptable to failure due to torque hence the other common name for Silver Maple - Crack Maple (because the branches crack off)  

 Several trees species are naturally conical in shape such as Katsura, little leaf linden, Tulip  and the conifers (spruce , pine , cedar).

Some large  trees are just meant to be Canopy trees such as Honey Locust, Clump Birch, or Norway Maple (as they get older) so  have adequate space for these trees if you go this route.  

 

 If the Primary Leader of any tree gets damaged or broken, there is a very good chance of losing the primary leader and resulting in multiple leaders.  This should be corrected with corrective pruning.  Consult with an Arborist if you feel this maybe happening to your tree.