Generally, a party to a civil action cannot appeal on the basis of some aspect of trial procedure to which it did not object

Harris v. Leikin Group Inc., 2014 ONCA 479:

 [53] As a general rule, a party to a civil action cannot appeal on the basis of some aspect of trial procedure to which it did not object or sit on an objection only to raise it once it learns of an unfavourable result: see Marshall v. Watson Wyatt & Co. (2002), 57 O.R. (3d) 813 (C.A.), at paras. 14-15; Leader Media Productions Ltd. v. Sentinel Hill Alliance Atlantis Equicap Limited Partnership (2008), 90 O.R. (3d) 561 (C.A.), leave to appeal refused, [2008] S.C.C.A. No. 394, at paras. 50-51.