To convert that into a percentage which many prefer just divide 1 by the number and times by 100. So 1.4 on Novak Djokovic would equate to 71.4% which is pretty high but not the worst odds I've seen regular for some popular teams, people like Lewis Hamilton etc. As Djokovic is over 30 and injuries can happen I would not have taken that bet personally and as said the returns start to be less attractive.
I do look for odds over 2 but its tending towards underdog bet at that point and you cant exactly expect to win, it would be quite arrogant to presume the crowd is always wrong but it does happen.
1.4 is probably the lowest I would take for a favorite, except perhaps if I am almost 90% certain my team or selection would win, in which case I would go for as low as 1.2x, but even so, rarely. All my favorite bets are around 1.5x and the funny thing is once it goes to 1.6 I don't feel like taking it then I go for 2x. I think a lot of people feel 1.6 means guaranteed but I think at that stage, you WANT 2x to get real value because they will probably lose 50/50 of those odds.
Yeah Hamilton was at one point 1.2 as I have seen, that is really not worth it at all. This is the difference between gambling and investment, people do mix these two things a lot usually and that is the funny side.
For example, 1.2 means that you will put in 100 dollars and get 120 dollars back, a 20% profit, normally if you tell a trader that there is a 20% profit chance for just a days worth of thing, they would jump all over it, they would take that trade every single time, but the difference in gambling is, if you lose you lose all that 100 dollars, so for a chance of 20% profit you put 100% loss chance up.
Now there are traders who would accept even that, and to think that is 1.2 which is rare, usually even guaranteed stuff go for 40% profit, they could potentially actually do that. However in gambling, it just doesn't worth it at all.