It is difficult to suggest someone about those things or works which can't done by us or we haven't any knowledge about and even we don't have information about ones ability,but after these facts we suggest them those things or work ,then we should have to ready to face difficulties from them as well as from others too.
But it  easy to to suggest someone about which we have already did or seen doing, and we completely know about that, then we can easily suggest someone about what is good...:)
Hope it will help you dear...! Then plz mark it best..Thanks..:)